CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY (DEFICIT) - USD ($) $ in Millions	Total	COMMON STOCK	RETAINED EARNINGS (ACCUMULATED DEFICIT)	RETAINED EARNINGS (ACCUMULATED DEFICIT) Cumulative Effect, Period of Adoption, Adjustment
Balance at beginning of period at Dec. 31, 2017		$ 10,050	$ (713)	$ 141
Increase (Decrease) in Stockholder's Equity
Net income	$ 1,665		1,665
Dividends	(1,275)		(1,275)
Balance at end of period at Dec. 31, 2018	9,868	10,050	(182)	22
Increase (Decrease) in Stockholder's Equity
Net income	1,827		1,827
Dividends	(1,600)		(1,600)
Balance at end of period at Dec. 31, 2019	10,117	10,050	67	$ 3
Increase (Decrease) in Stockholder's Equity
Net income	1,707		1,707
Dividends	(1,725)		(1,725)
Other			(4)
Balance at end of period at Dec. 31, 2020	$ 10,098	$ 10,050	$ 48