Shareholders' Equity Repurchase Activity (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020
Repurchase Activity [Abstract]
Stock Repurchased During Period, Shares			7.4
Stock Repurchased During Period, Value	$ 100	$ 100	$ 100
Stock Repurchase Program, Number of Shares Authorized to be Repurchased			$ 5,100
Treasury Stock Shares Acquired From Inception			224.0
Treasury Stock Value Acquired Cost Method From Inception			$ 9,000

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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