Shareholders' Equity - Changes in AOCI by Component (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			$ 6,639
Other comprehensive income (loss) before reclassifications	$ 197	$ 47	(11)	$ 203
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	4	8	(1)	(4)
Income (loss) before income taxes	222	182	160	240
Tax (provision) benefit	(34)	(40)	(30)	(44)
Net current period other comprehensive income (loss)	195	34	(9)	202
Ending balance	6,444		6,444
Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	4	8	(1)	(4)
Net investment income		16		16
Fair value gains (losses) on FG VIEs	(1)	(8)	(3)	(10)
Income (loss) before income taxes	3	16	(4)	2
Tax (provision) benefit	(1)	(3)	2	(1)
Total amount reclassified from AOCI, net of tax	2	13	(2)	1
Total Accumulated Other Comprehensive Income [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				93
Amounts reclassified from AOCI to:
Ending balance	333	295	333	295
Net Unrealized Gains (Losses) on Investments with no OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				59
Other comprehensive income (loss) before reclassifications	184	90	28	255
Amounts reclassified from AOCI to:
Net current period other comprehensive income (loss)	175	79	13	242
Ending balance	427	301	427	301
Net Unrealized Gains (Losses) on Investments with no OTTI [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	12	11	18	14
Net investment income		2		2
Fair value gains (losses) on FG VIEs	0	0	0	0
Income (loss) before income taxes	12	13	18	16
Tax (provision) benefit	(3)	(2)	(3)	(3)
Total amount reclassified from AOCI, net of tax	9	11	15	13
Net Unrealized Gains (Losses) on Investments with OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				94
Other comprehensive income (loss) before reclassifications	19	(40)	(42)	(47)
Amounts reclassified from AOCI to:
Net current period other comprehensive income (loss)	25	(48)	(27)	(43)
Ending balance	(41)	51	(41)	51
Net Unrealized Gains (Losses) on Investments with OTTI [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	(8)	(3)	(19)	(18)
Net investment income		14		14
Fair value gains (losses) on FG VIEs	0	0	0	0
Income (loss) before income taxes	(8)	11	(19)	(4)
Tax (provision) benefit	2	(3)	4	0
Total amount reclassified from AOCI, net of tax	(6)	8	(15)	(4)
Net Unrealized Gains (Losses) on FG VIE Liabilities with Recourse due to Instrument Specific Credit Risk [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				(31)
Other comprehensive income (loss) before reclassifications	(6)	(2)	3	(4)
Amounts reclassified from AOCI to:
Net current period other comprehensive income (loss)	(5)	4	5	4
Ending balance	(22)	(27)	(22)	(27)
Net Unrealized Gains (Losses) on FG VIE Liabilities with Recourse due to Instrument Specific Credit Risk [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	0	0	0	0
Net investment income		0		0
Fair value gains (losses) on FG VIEs	(1)	(8)	(3)	(10)
Income (loss) before income taxes	(1)	(8)	(3)	(10)
Tax (provision) benefit	0	2	1	2
Total amount reclassified from AOCI, net of tax	(1)	(6)	(2)	(8)
Cumulative Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				(37)
Other comprehensive income (loss) before reclassifications	0	(1)	0	(1)
Amounts reclassified from AOCI to:
Net current period other comprehensive income (loss)	0	(1)	0	(1)
Ending balance	(38)	(38)	(38)	(38)
Cumulative Translation Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	0	0	0	0
Net investment income		0		0
Fair value gains (losses) on FG VIEs	0	0	0	0
Income (loss) before income taxes	0	0	0	0
Tax (provision) benefit	0	0	0	0
Total amount reclassified from AOCI, net of tax	0	0	0	0
Cash Flow Hedge [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance				8
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI to:
Net current period other comprehensive income (loss)	0	0	0	0
Ending balance	7	8	7	8
Cash Flow Hedge [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amounts reclassified from AOCI to:
Net realized investment gains (losses)	0	0	0	0
Net investment income		0		0
Fair value gains (losses) on FG VIEs	0	0	0	0
Income (loss) before income taxes	0	0	0	0
Tax (provision) benefit	0	0	0	0
Total amount reclassified from AOCI, net of tax	0	0	0	$ 0
Previously Reported [Member] | Total Accumulated Other Comprehensive Income [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	138	261	342
Previously Reported [Member] | Net Unrealized Gains (Losses) on Investments with no OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	252	222	352
Previously Reported [Member] | Net Unrealized Gains (Losses) on Investments with OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(66)	99	48
Previously Reported [Member] | Net Unrealized Gains (Losses) on FG VIE Liabilities with Recourse due to Instrument Specific Credit Risk [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(17)	(31)	(27)
Previously Reported [Member] | Cumulative Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(38)	(37)	(38)
Previously Reported [Member] | Cash Flow Hedge [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	$ 7	$ 8	7
Revision of Prior Period, Adjustment [Member] | Total Accumulated Other Comprehensive Income [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			0
Revision of Prior Period, Adjustment [Member] | Net Unrealized Gains (Losses) on Investments with no OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			62
Revision of Prior Period, Adjustment [Member] | Net Unrealized Gains (Losses) on Investments with OTTI [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			(62)
Revision of Prior Period, Adjustment [Member] | Net Unrealized Gains (Losses) on FG VIE Liabilities with Recourse due to Instrument Specific Credit Risk [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			0
Revision of Prior Period, Adjustment [Member] | Cumulative Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			0
Revision of Prior Period, Adjustment [Member] | Cash Flow Hedge [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance			$ 0