Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Parent [Member]	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 16,865,000,000						$ 0
Stock Repurchased and Retired During Period, Value	202,000,000		$ 202,000,000		$ 202,000,000
December 31, 2017 at Dec. 31, 2016		$ 75,000,000	18,461,000,000	$ (2,919,000,000)	16,865,000,000	$ 1,248,000,000
Capital contributions	18,000,000		18,000,000		18,000,000
Adjustments To Additional Paid In Capital, Capital Contribution	(202,000,000)
Net income (loss)	(365,000,000)			(365,000,000)	(365,000,000)
Other comprehensive income (loss), net of income tax	148,000,000				148,000,000	148,000,000
March 31, 2018 at Mar. 31, 2017		75,000,000	18,681,000,000	(3,284,000,000)	16,868,000,000	1,396,000,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	16,868,000,000						0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest | Restatement Adjustment [Member]	16,888,000,000						15,000,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	16,868,000,000						15,000,000
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	20,000,000			35,000,000	20,000,000	(15,000,000)
Noncontrolling Interest, Period Increase (Decrease)	0				0
December 31, 2017 (Restatement Adjustment [Member])		75,000,000	19,073,000,000	(4,097,000,000)	16,873,000,000	1,822,000,000
December 31, 2017 at Dec. 31, 2017	16,853,000,000	75,000,000	19,073,000,000	(4,132,000,000)	16,853,000,000	1,837,000,000
Net income (loss)	(2,000,000)			(2,000,000)	(2,000,000)
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	(2,000,000)
Other comprehensive income (loss), net of income tax	(823,000,000)				(823,000,000)	(823,000,000)
March 31, 2018 at Mar. 31, 2018	16,048,000,000	$ 75,000,000	$ 19,073,000,000	$ (4,099,000,000)	$ 16,048,000,000	999,000,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 16,063,000,000						$ 15,000,000
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						$ 15,000,000