Quarterly Results - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Impairment of long-lived assets		$ 36		$ 36
Deferred tax asset valuation allowance release	$ 49	$ 100	$ 179
Impairment of equity affiliate	39			39
Other tax expense	$ 23			$ 23
Loss on disposal group held for sale			80		$ 80
Pension settlement charges			42		42
Loss on extinguishment of debt			$ 19	$ 2	$ 19