Equipment Held for Operating Lease (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) item region	Dec. 31, 2014 USD ($) aircraft item	Dec. 31, 2013 USD ($)
Equipment Held for Lease
Number of geographic regions in which aircraft lessees are domiciled in \| region	8
Lease rent revenue	$ 107,866	$ 101,748	$ 101,737
Lease rent revenue less applicable depreciation and interest	5,658	3,809	10,679
Net book value of equipment held for operating lease	1,122,859	1,066,448	1,033,022
Minimum future payments under non-cancelable leases
2016	74,133
2017	47,513
2018	35,467
2019	27,434
2020	21,914
Thereafter	24,689
Minimum future payments	231,150
United States
Equipment Held for Lease
Lease rent revenue	43,577	37,990	37,788
Lease rent revenue less applicable depreciation and interest	634	2,577	6,055
Net book value of equipment held for operating lease	103,492	61,521	103,515
Mexico
Equipment Held for Lease
Lease rent revenue	31,534	21,796	21,407
Lease rent revenue less applicable depreciation and interest	2,310	2,157	1,641
Net book value of equipment held for operating lease	42,246	64,770	75,628
Canada
Equipment Held for Lease
Lease rent revenue	9,688	9,907	8,794
Lease rent revenue less applicable depreciation and interest	(123)	(100)	747
Net book value of equipment held for operating lease	18,893	11,026	12,500
Europe
Equipment Held for Lease
Lease rent revenue	9,177	11,880	14,258
Lease rent revenue less applicable depreciation and interest	11,074	6,988	5,061
Net book value of equipment held for operating lease	389,721	344,833	368,381
South America
Equipment Held for Lease
Lease rent revenue	6,906	7,771	7,387
Lease rent revenue less applicable depreciation and interest	1,929	3,503	2,995
Net book value of equipment held for operating lease	112,718	107,080	78,486
Asia
Equipment Held for Lease
Lease rent revenue	2,789	4,997	2,947
Lease rent revenue less applicable depreciation and interest	8,867	5,891	5,652
Net book value of equipment held for operating lease	310,292	232,448	219,123
Africa
Equipment Held for Lease
Lease rent revenue	2,223	4,143	6,547
Lease rent revenue less applicable depreciation and interest	206	1,041	837
Net book value of equipment held for operating lease	9,612	12,063	3,734
Middle East
Equipment Held for Lease
Lease rent revenue	1,972	3,264	2,609
Lease rent revenue less applicable depreciation and interest	474	1,277	1,664
Net book value of equipment held for operating lease	18,937	17,125	58,509
Off-lease and other
Equipment Held for Lease
Lease rent revenue less applicable depreciation and interest	(19,713)	(19,525)	(13,973)
Net book value of equipment held for operating lease	$ 116,948	$ 215,582	$ 113,146
Equipment held for lease Member \| Engines and related equipment
Equipment Held for Lease
Number of equipments held for lease \| item	201	207
Cost of equipments held for lease	$ 1,310,700	$ 1,303,300
Equipment held for lease Member \| Spare parts packages
Equipment Held for Lease
Number of equipments held for lease \| item	5	5
Cost of equipments held for lease	$ 5,200	$ 6,100
Equipment held for lease Member \| Aircrafts
Equipment Held for Lease
Number of equipments held for lease	10	5
Cost of equipments held for lease	$ 123,500	$ 38,100
Month-to-month leases
Equipment Held for Lease
Net book value of equipment held for operating lease	90,173	97,951
Leases expiring 2015
Equipment Held for Lease
Net book value of equipment held for operating lease		331,757
Leases expiring 2016
Equipment Held for Lease
Net book value of equipment held for operating lease	434,658	151,444
Leases expiring 2017
Equipment Held for Lease
Net book value of equipment held for operating lease	113,879	73,387
Leases expiring 2018
Equipment Held for Lease
Net book value of equipment held for operating lease	87,916	62,972
Leases expiring 2019
Equipment Held for Lease
Net book value of equipment held for operating lease	60,022	24,001
Leases expiring 2020
Equipment Held for Lease
Net book value of equipment held for operating lease	88,634
Leases expiring thereafter
Equipment Held for Lease
Net book value of equipment held for operating lease	$ 130,629	$ 109,354

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39896-112707

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
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-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41457-112716

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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