Commitments And Contingencies Environmental Matters (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Environmental Exit Cost [Line Items]
Accrual for Environmental Loss Contingencies	$ 6	$ 4
Accrued Environmental Loss Contingencies, Noncurrent	5	3
Accrued Liabilities
Environmental Exit Cost [Line Items]
Accrued Environmental Loss Contingencies, Current	1	1
Other Long-Term Liabilities
Environmental Exit Cost [Line Items]
Accrued Environmental Loss Contingencies, Noncurrent	$ 5	3
Discontinued Operations | Liabilities Held for Sale
Environmental Exit Cost [Line Items]
Accrual for Environmental Loss Contingencies		$ 6