Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)	Net Parent (Deficit)	Accumulated Other Comprehensive Income
Beginning balance at Dec. 31, 2018	$ (1,027)			$ (1,034)	$ 7
Adoption of new accounting principle				(3)	3
Net income	17			17
Other comprehensive income (loss), net of income taxes	(1)				(1)
Net transfers (to) from Parent	12			12
Ending balance at Mar. 31, 2019	(999)			(1,008)	9
Beginning balance at Dec. 31, 2018	(1,027)			(1,034)	7
Adoption of new accounting principle					3
Net income	135
Other comprehensive income (loss), net of income taxes					(1)
Ending balance at Sep. 30, 2019	(798)			(807)	9
Beginning balance at Mar. 31, 2019	(999)			(1,008)	9
Net income	55			55
Net transfers (to) from Parent	34			34
Ending balance at Jun. 30, 2019	(910)			(919)	9
Net income	63			63
Net transfers (to) from Parent	49			49
Ending balance at Sep. 30, 2019	(798)			(807)	9
Beginning balance at Dec. 31, 2019	(818)			(823)	5
Net income	26		$ 20	6
Other comprehensive income (loss), net of income taxes	(2)				(2)
Net transfers (to) from Parent	855			855
Reclassification of net parent (deficit) in RCP		$ 38		(38)
Issuance of common stock, net of costs	1,339	1,339
Dividends	(31)		(31)
Other	1	1
Ending balance at Mar. 31, 2020	1,370	1,378	(11)		3
Beginning balance at Dec. 31, 2019	(818)			$ (823)	5
Net income	251
Other comprehensive income (loss), net of income taxes					(2)
Ending balance at Sep. 30, 2020	1,551	1,380	168		3
Beginning balance at Mar. 31, 2020	1,370	1,378	(11)		3
Net income	112		112
Other comprehensive income (loss), net of income taxes	1				1
Other	1	1
Ending balance at Jun. 30, 2020	1,484	1,379	101		4
Net income	113		113
Other comprehensive income (loss), net of income taxes	(1)				(1)
Dividends	(46)		(46)
Other	1	1
Ending balance at Sep. 30, 2020	$ 1,551	$ 1,380	$ 168		$ 3