Stockholders' Equity (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Shares repurchased	$ 91	$ 30
Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Shares repurchased (in shares)	9
Shares repurchased	$ 85
Stock repurchase program, remaining authorized repurchase amount	$ 1,300

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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