Finance Assets and Lessor Operating Leases (Lease Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Leases [Abstract]
Profit recognized at commencement	$ 34,320	$ 39,642	$ 70,678	$ 86,929
Interest income	58,045	60,855	117,523	122,687
Total lease income from sales-type leases	$ 92,365	$ 100,497	$ 188,201	$ 209,616

Amount of lease income from variable lease payments, interest income from net investment on sales-type lease, and profit (loss) recognized at commencement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration