Condensed Consolidated Statements of Changes in Shareholder's Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings (Deficit)	Previously Reported	Previously Reported Common Stock	Previously Reported Additional Paid-In Capital	Previously Reported Accumulated Other Comprehensive Income (Loss)	Previously Reported Retained Earnings (Deficit)
Beginning Balance at Dec. 31, 2015	$ 3,368	$ 3	$ 3,272	$ 386	$ (293)
Comprehensive income (loss):
Net income (loss)	113	0	0	0	113
Other comprehensive income (loss), after tax	173	0	0	173	0
Comprehensive income (loss)	286
Dividends paid and distributions of capital	(278)	0	(278)	0	0
Employee related benefits	0	0	0	0	0
Ending Balance at Dec. 31, 2016	3,376	3	2,994	559	(180)
Comprehensive income (loss):
Net income (loss)	210	0	0	0	210
Other comprehensive income (loss), after tax	259	0	0	259	0
Comprehensive income (loss)	469
Dividends paid and distributions of capital	(265)	0	(265)	0	0
Employee related benefits	1	0	1	0	0
Ending Balance at Dec. 31, 2017	3,581					$ 3,581	$ 3	$ 2,730	$ 818	$ 30
Increase (Decrease) in Stockholders' Equity
Cumulative Effect of New Accounting Principle in Period of Adoption | Adjustment for adoption of ASU 2014-09	72	0	0	0	72
Cumulative Effect of New Accounting Principle in Period of Adoption | Adjustment for adoption of ASU 2016-01	0	0	0	(12)	12
Stockholders' Equity Atrributable to Parent, Adjusted Balance	3,653	3	2,730	806	114
Comprehensive income (loss):
Net income (loss)	495	0	0	0	495
Other comprehensive income (loss), after tax	(698)	0	0	(698)	0
Comprehensive income (loss)	(203)
Dividends paid and distributions of capital	(126)	0	0	0	(126)
Employee related benefits	(2)	0	(2)	0	0
Ending Balance at Dec. 31, 2018	$ 3,322	$ 3	$ 2,728	$ 108	$ 483