Investments (Leveraged Leases - Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Leveraged leases, net of allowance for credit losses	$ 51	$ 64
Leveraged leases, allowance for credit losses	$ 13	$ 0
Leveraged leases by performance status as a percentage of leveraged leases	100.00%	100.00%

The net investment in arrangements meeting the criteria to be classified as leveraged excluding deferred taxes.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118948374&loc=SL77920254-209983

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45424-112738

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77907235&loc=d3e45152-112736

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant