| Long-Term Debt (Details)$ / shares in Units, € in Millions, shares in Millions
 |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |  | 
| May 08, 2020  USD ($) | Jul. 31, 2020  USD ($)  $ / shares | Jun. 30, 2020  USD ($) | May 31, 2020  USD ($)  D  $ / shares | Apr. 30, 2020  USD ($)  installment | Mar. 31, 2020  USD ($) | Jun. 30, 2020  USD ($) | Mar. 31, 2020  USD ($) | Jun. 30, 2020  USD ($)  shares | Jun. 30, 2019  USD ($) | Apr. 30, 2020  EUR (€) | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  | $ 1,088,923,000 |  |  |  | $ 1,088,923,000 |  | $ 1,088,923,000 |  |  | 
| Debt modification cost | $ 16,200,000 |  |  |  |  |  |  |  |  |  |  | 
| Loss on extinguishment of debt | $ 5,000,000.0 |  |  |  |  |  |  |  | 5,014,000 | $ 3,988,000 |  | 
| Beneficial conversion feature |  |  |  |  |  |  | 131,240,000 |  | 131,240,000 |  |  | 
| Outstanding principal amount of notes |  |  | $ 1,262,500,000 |  |  |  | $ 1,262,500,000 |  | 1,262,500,000 |  |  | 
| Interest expense, net |  |  |  |  |  |  |  |  | $ 12,529,000 |  |  | 
| Export Credit Backed Securities |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  |  |  | $ 386,000,000 |  |  |  |  |  |  | 
| Number of installments for amortization | installment |  |  |  |  | 8 |  |  |  |  |  |  | 
| Debt holiday period |  |  |  |  | 12 months |  |  |  |  |  |  | 
| Supplemental Agreement |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Annual debt repayment rate |  |  |  | 25 |  |  |  |  |  |  |  | 
| $675 Million Senior Secured Revolving Loan Facility |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  |  |  |  | $ 675,000,000 |  | $ 675,000,000 |  |  |  | 
| Maximum borrowing capacity |  |  |  |  |  | $ 675,000,000 |  | 675,000,000 |  |  |  | 
| Repayment of Epic credit facility |  | $ 675,000,000 |  |  |  |  |  |  |  |  |  | 
| $675 Million Senior Secured Revolving Loan Facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  |  | 0.80% |  |  |  |  |  | 
| $675 Million Senior Secured Revolving Loan Facility | Eurocurrency Loans | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  |  | 1.75% |  |  |  |  |  | 
| $675 Million Senior Secured Revolving Loan Facility | Base Rate Loans | Base rate loans |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  |  | 0.75% |  |  |  |  |  | 
| $230 Pride of America Term Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  |  | $ 230,000,000 |  |  |  |  |  |  | 
| $230 Pride of America Term Loan | Eurocurrency Loans | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.75% |  |  |  |  |  |  | 
| $230 Pride of America Term Loan | Base Rate Loans | Base rate loans |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 0.75% |  |  |  |  |  |  | 
| $260 Million Norwegian Jewel Term Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  | $ 260,000,000 |  |  |  |  |  |  |  | 
| Annual debt repayment rate |  |  |  | 25 |  |  |  |  |  |  |  | 
| $260 Million Norwegian Jewel Term Loan | Eurocurrency Loans | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  | 2.50% |  |  |  |  |  |  |  | 
| $260 Million Norwegian Jewel Term Loan | Base Rate Loans | Base rate loans |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  | 1.50% |  |  |  |  |  |  |  | 
| Private Exchangeable Notes |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  | $ 400,000,000 |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  |  |  | 100.00% |  |  |  |  |  |  |  | 
| Percentage of share price on debt instrument |  |  |  | 250.00% |  |  |  |  |  |  |  | 
| Number of specified trading days | D |  |  |  | 20 |  |  |  |  |  |  |  | 
| Number of consecutive trading days | D |  |  |  | 30 |  |  |  |  |  |  |  | 
| Debt instrument amount |  |  |  | $ 1,000 |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  |  |  | 82.6446 |  |  |  |  |  |  |  | 
| Initial exchange price | $ / shares |  |  |  | $ 12.10 |  |  |  |  |  |  |  | 
| Remaining discount amortization period |  |  |  |  |  |  |  |  | 5 years 10 months 24 days |  |  | 
| Percentage of Effective interest rate |  |  | 17.45% |  |  |  | 17.45% |  | 17.45% |  |  | 
| If-converted value above par value |  |  |  |  |  |  |  |  | $ 143,100,000 |  |  | 
| Shares available | shares |  |  |  |  |  |  |  |  | 33.1 |  |  | 
| Private Exchangeable Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  |  |  | 90.9090 |  |  |  |  |  |  |  | 
| Private Exchangeable Notes | Accreted Interest [Member] | Debt Instrument, First Year Post Issuance |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 7.00% |  |  |  |  |  |  |  | 
| Private Exchangeable Notes | Accreted Interest [Member] | Debt Instrument, Four Years Following First Year Post Issuance |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 4.50% |  |  |  |  |  |  |  | 
| Private Exchangeable Notes | Cash Interest | Debt Instrument, Four Years Following First Year Post Issuance |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 3.00% |  |  |  |  |  |  |  | 
| Private Exchangeable Notes | Cash Interest | Debt Instrument, Final Year Prior To Maturity |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 7.50% |  |  |  |  |  |  |  | 
| Senior Secured Notes Due 2024 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  | $ 675,000,000.0 |  |  |  |  |  |  |  | 
| Original issue discount and private offering |  |  |  | 99.00% |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 12.25% |  |  |  |  |  |  |  | 
| Percentage of principal amount of debt redeemed |  |  |  | 35.00% |  |  |  |  |  |  |  | 
| Percentage of thresholds, after percentage |  |  |  | 65.00% |  |  |  |  |  |  |  | 
| Senior Secured Notes Due 2024 | Debt Redemption Prior To February 15, 2024 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  |  |  | 100.00% |  |  |  |  |  |  |  | 
| Senior Secured Notes Due 2024 | Debt Redemption On Or After February 15, 2024 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  |  |  | 100.00% |  |  |  |  |  |  |  | 
| Senior Secured Notes Due 2024 | Debt Redemption Prior To February 15, 2022 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  |  |  | 112.25% |  |  |  |  |  |  |  | 
| Exchangeable Senior Secured Notes Due 2024 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  | $ 862,500,000 |  |  |  |  |  |  |  | 
| Interest Rate |  |  |  | 6.00% |  |  |  |  |  |  |  | 
| Debt instrument amount |  |  |  | $ 1,000 |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  |  |  | 72.7273 |  |  |  |  |  |  |  | 
| Initial exchange price | $ / shares |  |  |  | $ 13.75 |  |  |  |  |  |  |  | 
| Remaining discount amortization period |  |  |  |  |  |  |  |  | 3 years 10 months 24 days |  |  | 
| Percentage of Effective interest rate |  |  | 7.09% |  |  |  | 7.09% |  | 7.09% |  |  | 
| If-converted value above par value |  |  |  |  |  |  |  |  | $ 168,100,000 |  |  | 
| Shares available | shares |  |  |  |  |  |  |  |  | 62.7 |  |  | 
| Exchangeable Senior Secured Notes Due 2024 | Maximum |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  |  |  | 89.4454 |  |  |  |  |  |  |  | 
| Deferred Term A Loans | Fifth Amended And Restated Credit Agreement |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Percentage of outstanding loans held by lender | 87.57% |  |  |  |  |  |  |  |  |  |  | 
| Annual debt repayment rate | 25 |  |  |  |  |  |  |  |  |  |  | 
| Deferred Term A Loans | Fifth Amended And Restated Credit Agreement | Eurocurrency Loans | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate | 2.50% |  |  |  |  |  |  |  |  |  |  | 
| Deferred Term A Loans | Fifth Amended And Restated Credit Agreement | Base Rate Loans | Base rate loans |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate | 1.50% |  |  |  |  |  |  |  |  |  |  | 
| Deferred Loans | Supplemental Agreement |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  | $ 156,000,000 |  |  |  | $ 156,000,000 |  | $ 156,000,000 |  |  | 
| Explorer Newbuild Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  | 2.80% |  |  |  |  |  |  |  |  | 
| Splendor Newbuild Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  | 1.75% |  |  |  |  |  |  |  |  | 
| Marina Newbuild Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  | 0.55% |  |  |  |  |  |  |  |  | 
| Riviera Newbuild Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  | 0.55% |  |  |  |  |  |  |  |  | 
| EUR 529.8 Million Breakaway One Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | € 529.8 | 
| EUR 529.8 Million Breakaway One Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 0.90% |  |  |  |  |  |  | 
| EUR 529.8 Million Breakaway Two Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | 529.8 | 
| EUR 529.8 Million Breakaway Two Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.20% |  |  |  |  |  |  | 
| EUR 590.5 Million Breakaway Three Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | 590.5 | 
| EUR 590.5 Million Breakaway Three Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.50% |  |  |  |  |  |  | 
| EUR 729.9 Million Breakaway Four Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | 729.9 | 
| EUR 729.9 Million Breakaway Four Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.50% |  |  |  |  |  |  | 
| EUR 710.8 Million Seahawk 1 Term Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | 710.8 | 
| EUR 710.8 Million Seahawk 1 Term Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.00% |  |  |  |  |  |  | 
| EUR 748.7 Million Seahawk 2 Term Loan |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount | € |  |  |  |  |  |  |  |  |  |  | € 748.7 | 
| EUR 748.7 Million Seahawk 2 Term Loan | Six Months London Interbank Offered Rate Libor |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  | 1.00% |  |  |  |  |  |  | 
| Subsequent Event | 2025 Exchangeable Notes |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  | $ 450,000,000.0 |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  | 5.375% |  |  |  |  |  |  |  |  |  | 
| Debt instrument amount |  | $ 1,000 |  |  |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  | 53.3333 |  |  |  |  |  |  |  |  |  | 
| Initial exchange price | $ / shares |  | $ 18.75 |  |  |  |  |  |  |  |  |  | 
| Subsequent Event | 2025 Exchangeable Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Ordinary share exchange rate |  | 66.6666 |  |  |  |  |  |  |  |  |  | 
| Subsequent Event | 2026 Senior Secured Notes |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  | $ 750,000,000.0 |  |  |  |  |  |  |  |  |  | 
| Interest Rate |  | 10.25% |  |  |  |  |  |  |  |  |  | 
| Percentage of principal amount of debt redeemed |  | 35.00% |  |  |  |  |  |  |  |  |  | 
| Percentage of thresholds, after percentage |  | 65.00% |  |  |  |  |  |  |  |  |  | 
| Subsequent Event | 2026 Senior Secured Notes | Debt Redemption Prior To August 1, 2023 |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  | 100.00% |  |  |  |  |  |  |  |  |  | 
| Subsequent Event | 2026 Senior Secured Notes | Debt Redemption On Or Prior To August 1, 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Redemption price as a percentage of face amount |  | 110.25% |  |  |  |  |  |  |  |  |  | 
| NCLC |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount |  |  |  |  |  | $ 1,550,000,000 |  | 1,550,000,000 |  |  |  | 
| NCLC | $875 Million Senior Secured Revolving Loan Facility |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  |  |  |  | 875,000,000 |  | $ 875,000,000 |  |  |  | 
| NCLC | $875 Million Senior Secured Revolving Loan Facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Basis spread on variable rate |  |  |  |  |  |  |  | 1.50% |  |  |  | 
| NCLC | $675 Million Senior Secured Revolving Loan Facility |  |  |  |  |  |  |  |  |  |  |  | 
| Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  | 
| Principal amount outstanding |  |  |  |  |  | $ 675,000,000 |  | $ 675,000,000 |  |  |  |