Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Detail Textuals)

v3.8.0.1
Summary of Significant Accounting Policies (Detail Textuals)
$ in Thousands, shares in Millions
 12 Months Ended
Dec. 31, 2017
USD ($)
CruiseShip
segment
shares
Dec. 31, 2016
USD ($)
CruiseShip
shares
Dec. 31, 2015
USD ($)
shares
Schedule Of Significant Accounting Policies [Line Items]      
Reclassification of revenue from passenger ticket revenue to onboard and other revenue $ 21,900    
Allowance for doubtful accounts 5,900 $ 4,700  
Advertising costs included in prepaid expenses and other assets 2,400 1,300  
Expenses related to advertising costs $ 289,100 $ 270,500 $ 232,200
Antidilutive securities excluded from computation of earnings per share | shares 5.6 7.1 2.8
Reduction in estimated residual values, percentage 15.00%    
Gross basis revenue and expenses include port fees and taxes $ 327,400 $ 286,600 $ 243,800
Foreign currency transaction gain (loss) $ (14,200) 4,500 $ 11,000
Number of reportable segments | segment 1    
Number of cruises ships | CruiseShip 25    
Ship, carrying value $ 11,040,488 10,117,689  
US corporate income tax rate 35.00%    
Corporate income tax rate effective in 2018 21.00%    
Income tax expense due to reduction of deferred tax liabilties $ 7,400    
Goodwill 1,388,931 $ 1,388,931  
ASU No. 2016-16      
Schedule Of Significant Accounting Policies [Line Items]      
Cumulative effect adjustment to retained earnings 19,100    
Oceania Cruises      
Schedule Of Significant Accounting Policies [Line Items]      
Goodwill 523,000    
Regent Seven Seas      
Schedule Of Significant Accounting Policies [Line Items]      
Goodwill 462,100    
Norwegian Reporting Units      
Schedule Of Significant Accounting Policies [Line Items]      
Goodwill $ 403,800    
Revenue      
Schedule Of Significant Accounting Policies [Line Items]      
Percentage of revenue attributable to U.S.- sourced passengers 77.00% 81.00% 75.00%
Concentration risk, benchmark
No other individual country’s revenues exceeded 10% in any of our last three years.
No other individual country’s revenues exceeded 10% in any of our last three years.
No other individual country’s revenues exceeded 10% in any of our last three years.
Bahamas Registry      
Schedule Of Significant Accounting Policies [Line Items]      
Number of cruises ships | CruiseShip 17 16  
Ship, carrying value $ 8,000,000 $ 7,100,000  
Marshall Island Registry      
Schedule Of Significant Accounting Policies [Line Items]      
Number of cruises ships | CruiseShip 7 7  
Ship, carrying value $ 1,900,000 $ 1,900,000  
U.S. Registry      
Schedule Of Significant Accounting Policies [Line Items]      
Number of cruises ships | CruiseShip 1 1  
Ship, carrying value $ 300,000 $ 300,000