Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Definition

Amount remaining of a stock repurchase plan authorized.

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Stockholders' equity (Details Textual) - USD ($) $ / shares in Units, $ in Billions						3 Months Ended		6 Months Ended
	Jul. 28, 2015	Jun. 05, 2015	Mar. 06, 2015	Mar. 04, 2015	Dec. 17, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Subsequent Event [Line Items]
Common stock, dividends declared per share (in usd per share)				$ 0.79	$ 0.79
Amount available for stock repurchases under a board approved stock repurchase plan						$ 2.9		$ 2.9
Dividends paid per share (in usd per share)		$ 0.79	$ 0.79			$ 0.79	$ 0.61	$ 1.58	$ 1.22
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock, dividends declared per share (in usd per share)	$ 0.79