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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Name:	us-gaap_TreasuryStockValueAcquiredCostMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Equity - Treasury stock (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Oct. 22, 2018
Treasury stock:
Purchase/acquisition of treasury stock (in shares)	158	0
Repurchases of common stock (in dollars)	$ 14
Treasury Stock
Treasury stock:
Repurchases of common stock (in dollars)	$ 14
2018 Stock Repurchase Program
Treasury stock:
Shares authorized to be repurchased (in shares)			8,000