Income Taxes Level 4 (Details) - Deferred Tax Assets and Liabilities - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets
Non-pension post-employment	$ 5	$ 5
Accrued and other expenses	56	53
Deferred Tax Assets, Property, Plant and Equipment	4	1
Loss, expense, and credit carryforwards	488	477
Intangible Assets, Current	5	6
Pension and postretirement benefit liabilities	37	47
Gross deferred tax assets	595	589
Valuation allowance	(547)	(522)	$ (651)	$ (611)
Net deferred tax asset	48	67
Liabilities [Abstract]
Property, plant and equipment	(47)	(52)
Unrepatriated earnings of foreign subsidiaries	(10)	(9)
Intangible assets	(6)	(9)
Gross deferred tax liabilities	(63)	(70)
Net deferred tax liability	$ (15)	$ (3)