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.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Common Stock - Additional Information (Details) - 2016 Repurchase Program - USD ($)	12 Months Ended
	Dec. 31, 2019	May 09, 2019	Jul. 30, 2018	Nov. 08, 2017	Nov. 14, 2016
Common Stock Disclosure [Line Items]
Stock repurchase program, authorized amount		$ 3,000,000,000			$ 1,000,000,000
Stock repurchase program, increase in authorized amount		$ 1,000,000,000	$ 500,000,000	$ 500,000,000
Common stock, repurchased during the period	$ 393,000,000
Stock repurchase program, remaining amount	$ 1,052,000,000