Income Taxes Level 4 (Details) - Deferred Tax Assets and Liabilities - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Non-pension post-employment	$ 5	$ 5
Accrued and other expenses	53	94
Deferred Tax Assets, Property, Plant and Equipment	1	2
Loss and credit carryforwards	477	589
Intangible Assets, Current	6	6
Pension and postretirement benefit liabilities	47	51
Gross deferred tax assets	589	747
Valuation allowance	(522)	651	$ 611	$ 588
Net deferred tax asset	67	96
Liabilities [Abstract]
Property, plant and equipment	(52)	(71)
Unrepatriated earnings of foreign subsidiaries	(9)	(9)
Intangible assets	(9)	(19)
Gross deferred tax liabilities	(70)	(99)
Net deferred tax liability	$ (3)	$ (3)