Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

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The price paid per share to immediately purchase the targeted number of shares on the date of executing the accelerated share repurchase agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The cash outflow to reacquire common stock during the period.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Common Stock Repurchase Program (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		3 Months Ended
	Mar. 31, 2020	Feb. 29, 2020	Mar. 31, 2020	Mar. 31, 2019
Accelerated Share Repurchases [Line Items]
Cash paid for repurchase of common stock			$ 402	$ 68
Authorized share repurchases	$ 918		918
Accelerated Share Repurchase Agreement (ASR) [Member]
Accelerated Share Repurchases [Line Items]
Cash paid for repurchase of common stock		$ 313
Shares repurchased (in shares)	0.8	2.0
Weighted average per share purchase price	$ 111.78
Stock price (in dollars per share)		$ 125.75
10b5-1 Plan [Member]
Accelerated Share Repurchases [Line Items]
Cash paid for repurchase of common stock			$ 89
Shares repurchased (in shares)			0.9
Weighted average per share purchase price			$ 99.96