Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Billions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Jul. 22, 2016
Subsequent Event [Line Items]
Dividends declared per share (usd per share)	$ 0.28	$ 0.27	$ 0.55	$ 0.52
Subsequent Event [Member]
Subsequent Event [Line Items]
Stock repurchase program, authorized amount					$ 1.5