Schedule II (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Valuation and Qualifying Accounts [Abstract]
Valuation Allowances and Reserves, Balance	$ 119	$ 105	$ 112	$ 119
Net (credits) charges to expenses		10	5
Valuation Allowances and Reserves, Deductions		(15)	(12)
Valuation Allowances and Reserves, Charged to Other Accounts	$ 15	$ (2)	$ 0