Income Taxes - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Examination [Line Items]
Foreign tax credit valuation allowance released	$ 9,000,000
Sequestration of AMT credits		$ (2,000,000)	$ 3,000,000
Income taxes receivable	17,000,000	17,000,000
Increase / decrease in valuation allowance against deferred tax assets		(63,000,000)	124,000,000
Net deferred tax assets	241,000,000	241,000,000	283,000,000
Valuation allowance	112,000,000	112,000,000	175,000,000
Approximate federal net operating loss carryforwards	559,000,000	559,000,000
Foreign deferred tax assets	135,000,000	135,000,000
Minimum taxable income needed to fully realize the U.S. federal net deferred tax assets	1,285,000,000	1,285,000,000
State deferred tax assets	152,000,000	152,000,000
Annual U.S. federal NOL utilization	150,000,000	150,000,000
Unrecognized tax benefits, income tax penalties and interest	0	0	0
Total amounts of interest and penalties recognized in consolidated statements of operations		0	0	$ 0
Total amount of unrecognized tax benefit that would affect our effective tax rate	14,000,000	$ 14,000,000	$ 12,000,000	$ 14,000,000
Income tax examinations, possible period for resolution		12 months
Lapse of statutes of limitations	1,000,000	$ 1,000,000
Minimum
Income Tax Examination [Line Items]
Period of statutes of limitations		3 years
Maximum
Income Tax Examination [Line Items]
Period of statutes of limitations		5 years
Domestic Tax Authority
Income Tax Examination [Line Items]
Approximate federal alternative minimum tax credit carryforwards	17,000,000	$ 17,000,000
OMB
Income Tax Examination [Line Items]
Sequestration of AMT credits	$ 2,000,000