Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Available-for-sale securities	$ 94,331	$ 82,544
AFS securities allowance for credit losses	109	104
Mortgage loans allowance for credit losses	229	253
Mortgage loans	18,209	15,938
Investment funds	7,483	6,087
Accrued investment income, related party	1,010	905
Reinsurance recoverable, fair value portion	4,627	4,848
Other assets, consolidated variable interest entities	1,713	1,249
Interest sensitive contract liabilities	150,337	144,566
Future policy benefits	33,293	29,258
Funds withheld liability, fair value portion	437	452
Other liabilities	2,413	2,040
Accumulated other comprehensive income (related party: 2021 – $60 and 2020 – $59)	3,337	3,971
Investments, excluding investments in Related Party
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Available-for-sale securities	87,340	76,100
AFS securities allowance for credit losses	107	103
Mortgage loans allowance for credit losses	221	232
Mortgage loans	17,390	15,264
Investment funds	496	161
Investment funds	1,159	803
Funds withheld at interest	45,428	48,612
Short-term Investments, fair value portion	101	222
Other Investments allowance for credit losses	0	3
Other investments	1,680	572
Variable Interest Entities
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Other assets, consolidated variable interest entities	25	1
Other liabilities	243	134
Variable Interest Entities \| Investments, excluding investments in Related Party
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Mortgage loans	1,829	1,880
Investment funds	$ 348	$ 0
Preference Share, Series A
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Preferred stock, par value (in USD per share)	$ 1	$ 1
Aggregate liquidation preference	$ 863	$ 863
Preferred stock, authorized (in shares)	0.0	0.0
preferred stock, issued (in shares)	0.0	0.0
Preferred stock, outstanding (in shares)	0.0	0.0
Preference Share, Series B
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Preferred stock, par value (in USD per share)	$ 1	$ 1
Aggregate liquidation preference	$ 345	$ 345
Preferred stock, authorized (in shares)	0.0	0.0
preferred stock, issued (in shares)	0.0	0.0
Preferred stock, outstanding (in shares)	0.0	0.0
Preference Share, Series C
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Preferred stock, par value (in USD per share)	$ 1	$ 1
Aggregate liquidation preference	$ 600	$ 600
Preferred stock, authorized (in shares)	0.0	0.0
preferred stock, issued (in shares)	0.0	0.0
Preferred stock, outstanding (in shares)	0.0	0.0
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Common stock, par value (in USD per share)	$ 0.001	$ 0.001
Common stock authorized (in shares)	425.0	425.0
Common stock issued (in shares)	191.9	191.5
Common stock outstanding (in shares)	191.9	191.5
Series D Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Preferred stock, par value (in USD per share)	$ 1	$ 1
Aggregate liquidation preference	$ 575	$ 575
Preferred stock, authorized (in shares)	0.0	0.0
preferred stock, issued (in shares)	0.0	0.0
Preferred stock, outstanding (in shares)	0.0	0.0
Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Interest sensitive contract liabilities	$ 103,416	$ 98,945
Funds withheld liability, fair value portion	388	393
Fair Value \| Investments, excluding investments in Related Party
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Mortgage loans	17,883	15,811
Investment funds	663	642
Funds withheld at interest	44,055	46,668
Other investments	1,575	471
Recurring
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Investment funds		230
Recurring \| Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Reinsurance recoverable, fair value portion	1,946	2,100
Interest sensitive contract liabilities	14,823	14,181
Future policy benefits	2,294	2,376
Funds withheld liability, fair value portion	49	59
Recurring \| Fair Value \| Investments, excluding investments in Related Party
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Equity securities, at fair value	398	330
Mortgage loans	18	19
Investment funds	496	161
Funds withheld at interest	1,373	1,944
Short-term Investments, fair value portion	101	222
Other investments	105	105
Related Party
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Available-for-sale securities	6,991	6,444
AFS securities allowance for credit losses	2	1
Equity securities, at fair value	115	72
Mortgage loans allowance for credit losses	8	14
Mortgage loans	819	674
Investment funds	2,616	2,119
Investment funds	6,324	5,284
Funds withheld at interest	12,576	13,030
Other Investments allowance for credit losses	0	4
Other investments	147	469
Accrued investment income, related party	58	38
Interest sensitive contract liabilities	13,537	14,150
Future policy benefits	1,750	1,610
Other liabilities	105	112
Accumulated other comprehensive income (related party: 2021 – $60 and 2020 – $59)	60	59
Related Party \| Variable Interest Entities
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Investment funds	68	0
Related Party \| Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Mortgage loans	831	694
Investment funds	3,708	3,165
Funds withheld at interest	11,824	12,168
Other investments	151	499
Related Party \| Recurring \| Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Equity securities, at fair value	115	72
Investment funds	2,616	2,119
Funds withheld at interest	$ 752	$ 862

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