Income Taxes (Details 3) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Deferred and refundable income taxes	$ 89	$ 75
Deferred tax liabilities
Deferred income taxes and other liabilities	(939)	(812)
Deferred income taxes, net	$ (850)	$ (737)