Related Party Transactions (Schedule of Related Party Transactions, Revenues and Expenses) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Related Party Transaction [Line Items]
Total revenues and service charges	$ 226	$ 242	$ 736	$ 788
Interest income	0	0	0	1
Expenses	(74)	(62)	(168)	(180)
Dividends paid to noncontrolling interests	(14)	(36)	(216)	(227)
Liberty Group
Related Party Transaction [Line Items]
Total revenues and service charges	158	167	513	543
Equity method investees
Related Party Transaction [Line Items]
Total revenues and service charges	42	61	152	203
Other
Related Party Transaction [Line Items]
Total revenues and service charges	$ 26	$ 14	$ 71	$ 42

Payments Of Ordinary Dividends, Noncontrolling Interest, Related Parties

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874292-224272

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