Stockholder's Equity (Stock Repurchase Program) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	1 Months Ended	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2015		May. 28, 2015
Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract]
Stock repurchase program, authorized amount				$ 500
Purchase of treasury stock	1,000	1,000	[1]
Treasury stock acquired, average cost per share	$ 103.84
Stock repurchase program, remaining authorized repurchase amount	$ 396	$ 396

[1] Refer to “Stock Repurchase Program” section below for details.