Financing Receivables (Credit Quality Information Text) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Credit quality information [Line Items]
Nonperforming loans	$ 12	$ 9
Syndicated loans [Member]
Credit quality information [Line Items]
Nonperforming loans	0	1
Total loans, net	406	395
Commercial mortgage loans [Member]
Credit quality information [Line Items]
Nonperforming loans	$ 0	$ 0
Percent of commercial mortgage loans with highest risk rating	1.00%	1.00%
Total loans, net	$ 2,678	$ 2,672

Amount of financing receivable past due.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant