Capital Actions (Capital Actions) (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Capital Actions
Shares acquired for treasury	$ 506	$ 635
December 10, 2015 ASR \| March 2014 Repurchase Program
Capital Actions
Repurchase date	Dec. 14, 2015
Shares acquired for treasury	$ 215
Shares repurchased on repurchase date	9,248,482
Shares received from forward contract settlement	1,782,477
Total shares repurchased	11,030,959
Settlement date	Jan. 14, 2016
March 2, 2016 ASR \| March 2014 Repurchase Program
Capital Actions
Repurchase date	Mar. 04, 2016
Shares acquired for treasury	$ 240
Shares repurchased on repurchase date	12,623,762
Shares received from forward contract settlement	1,868,379
Total shares repurchased	14,492,141
Settlement date	Apr. 11, 2016
June 15, 2016 Open Market Share Repurchase \| March 2014 Repurchase Program
Capital Actions
Shares acquired for treasury	$ 26
Shares repurchased on repurchase date	1,436,100
Total shares repurchased	1,436,100
Settlement date	Jun. 20, 2016
August 03, 2016 ASR \| March 2016 Repurchase Program
Capital Actions
Repurchase date	Aug. 05, 2016
Shares acquired for treasury	$ 240
Shares repurchased on repurchase date	10,979,548
Shares received from forward contract settlement	1,099,205
Total shares repurchased	12,078,753
Settlement date	Nov. 07, 2016

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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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