Revenues - Narrative (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020		Sep. 30, 2021	Sep. 30, 2020		Dec. 31, 2020
Capitalized Contract Cost [Line Items]
Passenger ticket revenues	$ 456,958,000	$ (33,688,000)	[1]	$ 549,886,000	$ 2,174,667,000	[1]
Customer refunds	44,600,000			44,600,000			$ 95,800,000
Contract liability	538,600,000			538,600,000			124,800,000
Unredeemed future cruise credits	650,000,000			650,000,000
Contract asset	53,700,000			53,700,000			53,700,000
Commission, transportation and other
Capitalized Contract Cost [Line Items]
Prepaid travel agent commissions	51,400,000			$ 51,400,000			$ 1,100,000
Minimum
Capitalized Contract Cost [Line Items]
Length of cruise				2 days
Maximum
Capitalized Contract Cost [Line Items]
Length of cruise				24 days
Port Costs
Capitalized Contract Cost [Line Items]
Passenger ticket revenues	$ 29,300,000	$ 0		$ 33,900,000	$ 124,500,000

[1] Onboard and other revenues for the quarter and nine months ended September 30, 2020 includes a charge of $67.9 million to correct cancellation revenue, for certain immaterial bookings, which was incorrectly recognized during the six months ended June 30, 2020. The charge is considered immaterial to our financial statements.