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Settlement date of the forward contract indexed to issuer's equity, in CCYY-MM-DD format.

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Capital Actions - Capital Actions ASRs (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Capital Actions
Shares acquired for treasury	$ (350)			$ (500)	$ (1,463)	$ (1,053)
August 2019 ASR
Capital Actions
Repurchase Date	Aug. 07, 2019
Shares acquired for treasury	$ 100
Shares repurchased on repurchase date	3,150,482
Shares received from forward contract settlement	694,238
Total shares repurchased	3,844,720
Settlement date	Aug. 16, 2019
August 2019 ASR II
Capital Actions
Repurchase Date	Aug. 09, 2019
Shares acquired for treasury	$ 200
Shares repurchased on repurchase date	6,405,426
Shares received from forward contract settlement	1,475,487
Total shares repurchased	7,880,913
Settlement date	Aug. 28, 2019
Accelerated Share Repurchase Program
Capital Actions
Repurchase Date		Apr. 29, 2019	Mar. 27, 2019
Shares acquired for treasury		$ 200	$ 913
Shares repurchased on repurchase date		6,015,570	31,779,280
Shares received from forward contract settlement		1,217,805	2,026,584
Total shares repurchased		7,233,375	33,805,864
Settlement date		May 23, 2019	Jun. 28, 2019
Settlement date, secondary		May 24, 2019