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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) (Details 1) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		36 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 04, 2018	Sep. 16, 2015
September 2015 Share Repurchase Program Original Authorization
Share Repurchase [Line Items]
Amount Authorized					$ 4,000
Shares Retired			12.4
Average Cost Per Share			$ 241.36
Shares Repurchased	1.1	0.0
Share Repurchases - Notes to Table
Shares repurchased amount			$ 3,000
Amount remaining under authorization for share repurchases	$ 1,000		$ 1,000
December 2018 Share Repurchase Original Authorization [Member]
Share Repurchase [Line Items]
Amount Authorized				$ 3,000
Shares Retired	0.0
Average Cost Per Share	$ 0.00