Equity (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ (4)
Balance beginning of period	$ 718	$ 1,837	1,248
OCI before reclassifications	3,273	(1,382)	386
Deferred income tax benefit (expense)	(685)	382	(155)
AOCI before reclassifications, net of income tax	3,306	758	1,479
Amounts reclassified from AOCI	(115)	45	47
Deferred income tax benefit (expense)	24	(85)	311
Amounts reclassified from AOCI, net of income tax	(91)	(40)	358
Balance end of period	3,215	718	1,837
Unrealized Investment Gains (Losses), Net of Related Offsets
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			(79)
Balance beginning of period	564	1,709	1,019
OCI before reclassifications	3,224	(1,534)	529
Deferred income tax benefit (expense)	(677)	327	(206)
AOCI before reclassifications, net of income tax	3,111	423	1,342
Amounts reclassified from AOCI	(57)	179	61
Deferred income tax benefit (expense)	12	(38)	306
Amounts reclassified from AOCI, net of income tax	(45)	141	367
Balance end of period	3,066	564	1,709
Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Balance beginning of period	180	151	258
OCI before reclassifications	37	156	(152)
Deferred income tax benefit (expense)	(8)	54	54
AOCI before reclassifications, net of income tax	209	361	160
Amounts reclassified from AOCI	(58)	(134)	(14)
Deferred income tax benefit (expense)	12	(47)	5
Amounts reclassified from AOCI, net of income tax	(46)	(181)	(9)
Balance end of period	163	180	151
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Balance beginning of period	(26)	(23)	(29)
OCI before reclassifications	12	(4)	9
Deferred income tax benefit (expense)	0	1	(3)
AOCI before reclassifications, net of income tax	(14)	(26)	(23)
Amounts reclassified from AOCI	0	0	0
Deferred income tax benefit (expense)	0	0	0
Amounts reclassified from AOCI, net of income tax	0	0	0
Balance end of period	$ (14)	(26)	(23)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			(79)
Restatement Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning of period		1,758
Balance end of period			1,758
Restatement Adjustment | Unrealized Investment Gains (Losses), Net of Related Offsets
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning of period		1,630
Balance end of period			1,630
Restatement Adjustment | Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning of period		151
Balance end of period			151
Restatement Adjustment | Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning of period		$ (23)
Balance end of period			(23)
Adjustments for New Accounting Pronouncement [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Adjustments for New Accounting Pronouncement [Member] | Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			330
Adjustments for New Accounting Pronouncement [Member] | AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 330