Stock Repurchase Program, Authorized Amount, Approved Increase

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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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Amount of stock repurchase plan authorized.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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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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Total cost of shares repurchased divided by the total number of shares repurchased.

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Stockholders' Equity , Share Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share Repurchase Program [Line Items]
Stock repurchased in the period, aggregate purchase price		$ 26,500,000	$ 1,046,000,000.0	$ 117,400,000
Repurchase Program [Member]
Share Repurchase Program [Line Items]
Increase in authorized stock repurchase amount	$ 500,000,000.0
Stock repurchase program, authorized amount	$ 3,000,000,000.0
Stock repurchased in the period (in shares)			11.4
Stock repurchased, average price (in dollars per share)			$ 91.55
Stock repurchased in the period, aggregate purchase price			$ 1,050,000,000.00
Stock repurchase program, unused balance			$ 1,050,000,000.00