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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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Date the debt instrument was repurchased, in CCYY-MM-DD format.

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

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- Definition

Additional shared included in the calculation of diluted EPS as a result of the potentially dilutive effect of equity forward arrangements using the reverse treasury stock method.

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Number of stock bought back by the entity at the exercise price or redemption price.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Capital Actions - Capital Actions ASRs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Capital Actions [Line Items]
Shares acquired for treasury	$ (200)	$ (235)		$ (1,113)	$ (553)
March 2019 ASR \| March 2018 Repurchase Program
Capital Actions [Line Items]
Repurchase Date			Mar. 27, 2019
Shares acquired for treasury			$ 913
Shares repurchased on repurchase date			31,779,280
Shares received from forward contract settlement			2,026,584
Total shares repurchased			33,805,864
Settlement date			Jun. 28, 2019
April 2019 ASR \| March 2018 Repurchase Program
Capital Actions [Line Items]
Repurchase Date			Apr. 29, 2019
Shares acquired for treasury			$ 200
Shares repurchased on repurchase date			6,015,570
Shares received from forward contract settlement			1,217,805
Total shares repurchased			7,233,375
Settlement date			May 23, 2019
Settlement date, secondary			May 24, 2019