Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Geographic information (Lease revenues by individual countries) (Details)

v3.8.0.1
Geographic information (Lease revenues by individual countries) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Segment Reporting Information [Line Items]      
Lease revenue $ 4,713,802 $ 4,867,623 $ 4,991,551
Geographic Concentration Risk | Total Lease Revenue      
Segment Reporting Information [Line Items]      
Percentage of lease revenue 100.00% 100.00% 100.00%
China      
Segment Reporting Information [Line Items]      
Lease revenue $ 648,343 $ 669,859 $ 656,809
China | Geographic Concentration Risk | Total Lease Revenue      
Segment Reporting Information [Line Items]      
Percentage of lease revenue 13.80% 13.80% 13.20%
United States      
Segment Reporting Information [Line Items]      
Lease revenue $ 568,999 $ 535,526 $ 538,686
United States | Geographic Concentration Risk | Total Lease Revenue      
Segment Reporting Information [Line Items]      
Percentage of lease revenue 12.10% 11.00% 10.80%
Ireland      
Segment Reporting Information [Line Items]      
Lease revenue $ 120,500 $ 117,259 $ 58,571
Ireland | Geographic Concentration Risk | Total Lease Revenue      
Segment Reporting Information [Line Items]      
Percentage of lease revenue 2.60% 2.40% 1.20%
Other Countries      
Segment Reporting Information [Line Items]      
Lease revenue $ 3,375,960 $ 3,544,979 $ 3,737,485
Other Countries | Geographic Concentration Risk | Total Lease Revenue      
Segment Reporting Information [Line Items]      
Percentage of lease revenue 71.50% 72.80% 74.80%