Equity (Narrative) (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Value, Acquired, Cost Method	$ 1	$ 156
Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Shares, Acquired		1,000
Treasury Stock, Value, Acquired, Cost Method		$ 153
Stock Repurchase Program, Authorized Amount	$ 400

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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Balance Type:	debit
Period Type:	duration