CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Passenger ticket revenues	$ 1,581,385	$ 1,516,530	$ 2,999,608	$ 2,894,697
Onboard and other revenues	613,889	588,732	1,204,226	1,128,360
Total revenues	2,195,274	2,105,262	4,203,834	4,023,057
Cruise operating expenses:
Commissions, transportation and other	340,331	334,568	650,579	659,458
Onboard and other	132,437	136,198	238,431	239,852
Payroll and related	210,362	230,433	426,097	457,874
Food	121,764	124,517	242,975	246,027
Fuel	170,748	176,649	348,162	352,511
Other operating	281,143	308,222	526,365	596,443
Total cruise operating expenses	1,256,785	1,310,587	2,432,609	2,552,165
Marketing, selling and administrative expenses	283,855	290,782	601,320	593,108
Depreciation and amortization expenses	234,937	221,620	470,686	432,384
Operating Income	419,697	282,273	699,219	445,400
Other income (expense):
Interest income	5,811	5,683	12,063	8,403
Interest expense, net of interest capitalized	(76,632)	(78,747)	(156,949)	(144,193)
Equity investment income	23,359	27,268	35,239	48,292
Other expense (including a $21.7 million loss related to the 2016 elimination of the Pullmantur reporting lag)	(2,709)	(6,572)	(5,320)	(28,857)
Total other income (expense)	(50,171)	(52,368)	(114,967)	(116,355)
Net Income	$ 369,526	$ 229,905	$ 584,252	$ 329,045
Earnings per Share:
Basic (in dollars per share)	$ 1.72	$ 1.07	$ 2.72	$ 1.52
Diluted (in dollars per share)	$ 1.71	$ 1.06	$ 2.71	$ 1.52
Weighted-Average Shares Outstanding:
Basic (in shares)	215,085	215,265	214,978	216,089
Diluted (in shares)	216,062	216,131	215,944	217,040
Comprehensive Income
Net Income	$ 369,526	$ 229,905	$ 584,252	$ 329,045
Other comprehensive income (loss):
Foreign currency translation adjustments	5,979	(2,268)	8,321	4,380
Change in defined benefit plans	(3,649)	(3,585)	(4,290)	(7,097)
Gain on cash flow derivative hedges	128,954	156,351	151,415	159,088
Total other comprehensive income	131,284	150,498	155,446	156,371
Comprehensive Income	$ 500,810	$ 380,403	$ 739,698	$ 485,416