Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	50	50
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized	1,000	1,000
Common stock, shares issued	833	833
Common stock, shares outstanding	764	764
Treasury stock, shares	69	69
Accounts receivable, provision for credit loss, current	$ 271	$ 282

Amount of allowance for credit loss on accounts receivable, classified as current.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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