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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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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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Earnings Per Share, Share Repurchases and Dividends on Common Stock (Unaudited) Share Repurchases (Details 2) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	4 Months Ended	6 Months Ended		47 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Feb. 29, 2020	Dec. 04, 2018	Sep. 16, 2015
September 2015 Share Repurchase Program Original Authorization
Share Repurchase [Line Items]
Amount Authorized						$ 4,000
Shares Retired				15.4
Average Cost Per Share				$ 260.33
Shares Repurchased		0.9	1.7
December 2018 Share Repurchase Original Authorization [Member]
Share Repurchase [Line Items]
Amount Authorized					$ 3,000
Shares Retired	0.5
Average Cost Per Share	$ 326.20
Shares Repurchased		0.5
Share Repurchases - Notes to Table
Shares repurchased amount	$ 200
Amount remaining under authorization for share repurchases	$ 2,800	$ 2,800