Basis of Preparation and Critical Accounting Policies (Details) $ in Thousands	Jun. 30, 2018 USD ($) aircraft	Dec. 31, 2017 USD ($)
Maintenance Rights
Lease asset	$ 14,864,244	$ 13,280,250
Total cost	16,962,768	15,100,040
Maintenance Right Assets
Maintenance Rights
Lease asset	$ 55,600	$ 44,600
Aircraft Improvement Assets
Maintenance Rights
Number of aircraft purchased \| aircraft	9
Subject to existing lease
Maintenance Rights
Number of aircraft purchased \| aircraft	2
Total cost	$ 73,300
Subject to existing lease \| Maintenance Right Assets
Maintenance Rights
Total cost	$ 13,200

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41457-112716

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

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Balance Type:	debit
Period Type:	instant