Stockholders' Equity Table Of Changes In AOCI (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Beginning Balance			$ (199)
Other comprehensive income (loss)	$ 29	$ 2	23	$ 5
Total, Ending Balance	(176)		(176)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Beginning Balance			(199)
Other comprehensive income (loss) before reclassifications			9
Amounts reclassified from accumulated other comprehensive income (loss)			14
Other comprehensive income (loss)	29	$ 2	23	$ 5
Total, Ending Balance	(176)		(176)
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Beginning Balance			(2)
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from accumulated other comprehensive income (loss)			0
Other comprehensive income (loss)			0
Total, Ending Balance	(2)		(2)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Beginning Balance			(1)
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from accumulated other comprehensive income (loss)			0
Other comprehensive income (loss)			0
Total, Ending Balance	(1)		(1)
Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Beginning Balance			(196)
Other comprehensive income (loss) before reclassifications			9
Amounts reclassified from accumulated other comprehensive income (loss)			14
Other comprehensive income (loss)			23
Total, Ending Balance	$ (173)		$ (173)