Consolidated Statement of Shareholder's Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]
Beginning balance at Dec. 31, 2016	$ 2,209	$ 0	$ 161	$ (1,263)	$ 3,311
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(603)				(603)
Other comprehensive income (loss)	265			265
Ending balance at Dec. 31, 2017	1,871	0	161	(998)	2,708
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	387				387
Other comprehensive income (loss)	(62)			(62)
Ending balance at Dec. 31, 2018	2,196	0	161	(1,060)	3,095
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	418				418
Other comprehensive income (loss)	(27)			(27)
Ending balance at Dec. 31, 2019	$ 2,587	$ 0	$ 161	$ (1,087)	$ 3,513