Stockholders' Equity - Share Repurchase Program (Details) - USD ($) shares in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Jan. 31, 2020	Dec. 31, 2019
Equity [Abstract]
Remaining authorized repurchase amount	$ 13,660,000,000			$ 4,900,000,000
Share repurchase program, authorized amount			$ 10,000,000,000.0
Shares repurchased and retired (in shares)	6
Shares repurchased and retired	$ 1,242,000,000	$ 521,000,000

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Balance Type:	debit
Period Type:	duration