Divestitures (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		12 Months Ended
	Jan. 31, 2011	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Divestitures and Assets Held for Sale [Abstract]
Purchase price for divestiture of business/controlling interest	$ 1,500
Proceeds from business divestitures, net of costs		$ 0	$ 12	$ 30	$ 10	$ 1,450