Commitments and Contingencies - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($) ship berth	Dec. 31, 2017	Jul. 31, 2016 ft²
Commitments and Contingencies
Number of months considered to determine requirement of prepayment of debts	24 months
Cruise ships on order
Commitments and Contingencies
Aggregate cost of ships on order, not including TUI cruises on order | $	$ 12,200.0
Deposit for the purchase of ships expected to enter service | $	$ 656.8
Percentage of aggregate cost exposed to fluctuations in the euro exchange rate	54.30%	54.00%
Silversea Cruises | Cruise ships on order
Commitments and Contingencies
Number of ships under construction	2
Ship passenger capacity berths | berth	1,100
Line of Credit | Minimum
Commitments and Contingencies
Debt instrument covenant, minimum percentage of ownership by a person	50.00%
Debt Securities | Minimum
Commitments and Contingencies
Debt instrument covenant, minimum percentage of ownership by a person	50.00%
Port of Miami Terminal
Commitments and Contingencies
Area of real estate property | ft²			170,000
Operating lease term			5 years
Royal Caribbean International Cruise Ships | Quantum Class Ship | Cruise ships on order
Commitments and Contingencies
Number of ships under construction	2
Royal Caribbean International Cruise Ships | Oasis Class Ship | Cruise ships on order
Commitments and Contingencies
Number of ships under construction	1
Royal Caribbean International Cruise Ships | Project Icon ships | Cruise ships on order
Commitments and Contingencies
Number of ships under construction	2
Ship passenger capacity berths | berth	25,300
Celebrity Cruise Ships | Project Edge Class Ships | Cruise ships on order
Commitments and Contingencies
Number of ships under construction	4
Ship passenger capacity berths | berth	12,300