Fair Value - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Assets
Available-for-sale securities	$ 129,700	$ 112,225
Investment funds	16,818	14,128
Derivative assets	4,571	3,309
Restricted cash	1,218	628
Reinsurance recoverable	4,058	4,358
Other assets (related party: 2023 – $184 and 2022 – $161)	8,628	8,693
Liabilities
Interest sensitive contract liabilities	189,065	173,616	$ 166,878
Future policy benefits	46,672	42,110	41,285
Market risk benefits	3,021	2,970	$ 2,791
Derivative liabilities	1,892	1,646
Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	115,715	102,404
Trading securities, at fair value	1,592	1,595
Mortgage loans	37,978	27,454
Investment funds	124	79
Funds withheld at interest	(25,953)	(32,880)
Derivative assets	4,571	3,309
Short-term investments	527	2,160
Other investments	947	773
Related Party
Assets
Available-for-sale securities	13,985	9,821
Trading securities, at fair value	871	878
Equity securities, at fair value	304	279
Mortgage loans	1,234	1,302
Investment funds	1,604	1,569
Funds withheld at interest	(6,620)	(9,808)
Short-term investments	949	0
Other investments	327	303
Other assets (related party: 2023 – $184 and 2022 – $161)	184	161
Liabilities
Interest sensitive contract liabilities	9,055	11,889
Future policy benefits	3	1,353
Market risk benefits	183	195
Variable Interest Entities
Assets
Trading securities, at fair value	2,133	1,063
Mortgage loans	2,042	2,055
Investment funds	15,090	12,480
Other investments	94	101
Other assets (related party: 2023 – $184 and 2022 – $161)	99	112
U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	4,260	2,577
US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	962	927
Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	915	907
Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	67,301	60,901
Corporate | Related Party
Assets
Available-for-sale securities	1,356	982
CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	18,926	16,493
CLO | Related Party
Assets
Available-for-sale securities	4,235	3,079
ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	10,807	10,527
ABS | Related Party
Assets
Available-for-sale securities	8,394	5,760
CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	5,496	4,158
RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	7,048	5,914
Level 3
Assets
Mortgage loans	41,254	30,811
Recurring | Level 1
Assets
Cash and cash equivalents	9,996	7,779
Restricted cash	1,218	628
Reinsurance recoverable	0
Other assets (related party: 2023 – $184 and 2022 – $161)	0
Total assets measured at fair value	16,000	11,588
Liabilities
Market risk benefits	0	0
Derivative liabilities	43	38
Other liabilities		0
Total liabilities measured at fair value	43	38
Recurring | Level 1 | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	4,262	2,570
Trading securities, at fair value	22	23
Equity securities, at fair value	198	150
Mortgage loans	0	0
Derivative assets	93	42
Short-term investments	0	29
Other investments	0	0
Recurring | Level 1 | Related Party
Assets
Available-for-sale securities	0	0
Trading securities, at fair value	0	0
Equity securities, at fair value	59	0
Mortgage loans	0	0
Investment funds	0	0
Other investments	0	0
Reinsurance recoverable		0
Recurring | Level 1 | Variable Interest Entities
Assets
Trading securities, at fair value	0	5
Mortgage loans	0	0
Investment funds	0	0
Other investments	0	0
Cash and cash equivalents	152	362
Recurring | Level 1 | Related Party
Assets
Other assets (related party: 2023 – $184 and 2022 – $161)		0
Recurring | Level 1 | Universal life
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | Level 1 | AmerUs Closed Block
Liabilities
Future policy benefits	0	0
Recurring | Level 1 | ILICO Closed Block and life benefits
Liabilities
Future policy benefits	0	0
Recurring | Level 1 | Embedded derivatives
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | Level 1 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Funds withheld at interest		0
Recurring | Level 1 | Embedded derivatives | Related Party
Assets
Funds withheld at interest		0
Recurring | Level 1 | U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	4,253	2,570
Recurring | Level 1 | US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	9	0
Recurring | Level 1 | Corporate | Related Party
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | CLO | Related Party
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | ABS | Related Party
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 1 | RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 2
Assets
Cash and cash equivalents	0	0
Restricted cash	0	0
Reinsurance recoverable	0
Other assets (related party: 2023 – $184 and 2022 – $161)	0
Total assets measured at fair value	116,203	102,927
Liabilities
Market risk benefits	0	0
Derivative liabilities	1,848	1,607
Other liabilities	(89)	(77)
Total liabilities measured at fair value	1,759	1,530
Recurring | Level 2 | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	104,125	93,069
Trading securities, at fair value	1,538	1,519
Equity securities, at fair value	644	845
Mortgage loans	0	0
Derivative assets	4,478	3,267
Short-term investments	398	455
Other investments	286	170
Recurring | Level 2 | Related Party
Assets
Available-for-sale securities	4,457	3,164
Trading securities, at fair value	0	0
Equity securities, at fair value	0	0
Mortgage loans	0	0
Investment funds	0	0
Other investments	0	0
Reinsurance recoverable		0
Recurring | Level 2 | Variable Interest Entities
Assets
Trading securities, at fair value	275	436
Mortgage loans	0	0
Investment funds	0	0
Other investments	2	2
Cash and cash equivalents	0	0
Recurring | Level 2 | Related Party
Assets
Other assets (related party: 2023 – $184 and 2022 – $161)		0
Recurring | Level 2 | Universal life
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | Level 2 | AmerUs Closed Block
Liabilities
Future policy benefits	0	0
Recurring | Level 2 | ILICO Closed Block and life benefits
Liabilities
Future policy benefits	0	0
Recurring | Level 2 | Embedded derivatives
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | Level 2 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Funds withheld at interest		0
Recurring | Level 2 | Embedded derivatives | Related Party
Assets
Funds withheld at interest		0
Recurring | Level 2 | U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	7	7
Recurring | Level 2 | US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	962	927
Recurring | Level 2 | Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	869	906
Recurring | Level 2 | Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	64,911	59,236
Recurring | Level 2 | Corporate | Related Party
Assets
Available-for-sale securities	170	170
Recurring | Level 2 | CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	18,926	16,493
Recurring | Level 2 | CLO | Related Party
Assets
Available-for-sale securities	3,732	2,776
Recurring | Level 2 | ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	6,181	5,660
Recurring | Level 2 | ABS | Related Party
Assets
Available-for-sale securities	555	218
Recurring | Level 2 | CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	5,484	4,158
Recurring | Level 2 | RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	6,785	5,682
Recurring | Level 3
Assets
Cash and cash equivalents	0	0
Restricted cash	0	0
Reinsurance recoverable	1,301
Other assets (related party: 2023 – $184 and 2022 – $161)	431
Total assets measured at fair value	60,439	46,063
Liabilities
Market risk benefits	3,021	2,970
Derivative liabilities	1	1
Other liabilities	213	142
Total liabilities measured at fair value	12,970	11,495
Recurring | Level 3 | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	7,328	6,765
Trading securities, at fair value	32	53
Equity securities, at fair value	74	92
Mortgage loans	37,978	27,454
Derivative assets	0	0
Short-term investments	129	36
Other investments	477	441
Recurring | Level 3 | Related Party
Assets
Available-for-sale securities	9,528	6,657
Trading securities, at fair value	871	878
Equity securities, at fair value	245	279
Mortgage loans	1,234	1,302
Investment funds	1,043	959
Other investments	327	303
Reinsurance recoverable		1,388
Recurring | Level 3 | Variable Interest Entities
Assets
Trading securities, at fair value	1,858	622
Mortgage loans	2,042	2,055
Investment funds	1,402	2,471
Other investments	92	99
Cash and cash equivalents	0	0
Recurring | Level 3 | Related Party
Assets
Other assets (related party: 2023 – $184 and 2022 – $161)		481
Recurring | Level 3 | Universal life
Liabilities
Interest sensitive contract liabilities	739	829
Recurring | Level 3 | AmerUs Closed Block
Liabilities
Future policy benefits	1,100	1,164
Recurring | Level 3 | ILICO Closed Block and life benefits
Liabilities
Future policy benefits	551	548
Recurring | Level 3 | Embedded derivatives
Liabilities
Interest sensitive contract liabilities	7,345	5,841
Recurring | Level 3 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Funds withheld at interest		4,847
Recurring | Level 3 | Embedded derivatives | Related Party
Assets
Funds withheld at interest		(1,425)
Recurring | Level 3 | U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 3 | US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 3 | Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	46	1
Recurring | Level 3 | Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	2,381	1,665
Recurring | Level 3 | Corporate | Related Party
Assets
Available-for-sale securities	1,186	812
Recurring | Level 3 | CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | Level 3 | CLO | Related Party
Assets
Available-for-sale securities	503	303
Recurring | Level 3 | ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	4,626	4,867
Recurring | Level 3 | ABS | Related Party
Assets
Available-for-sale securities	7,839	5,542
Recurring | Level 3 | CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	12	0
Recurring | Level 3 | RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	263	232
Recurring | NAV
Assets
Cash and cash equivalents	0	0
Restricted cash	0	0
Reinsurance recoverable	0
Other assets (related party: 2023 – $184 and 2022 – $161)	0
Total assets measured at fair value	13,688	10,009
Liabilities
Market risk benefits	0	0
Derivative liabilities	0	0
Other liabilities		0
Total liabilities measured at fair value	0	0
Recurring | NAV | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Trading securities, at fair value	0	0
Equity securities, at fair value	0	0
Mortgage loans	0	0
Derivative assets	0	0
Short-term investments	0	0
Other investments	0	0
Recurring | NAV | Related Party
Assets
Available-for-sale securities	0	0
Trading securities, at fair value	0	0
Equity securities, at fair value	0	0
Mortgage loans	0	0
Investment funds	0	0
Other investments	0	0
Reinsurance recoverable		0
Recurring | NAV | Variable Interest Entities
Assets
Trading securities, at fair value	0	0
Mortgage loans	0	0
Investment funds	13,688	10,009
Other investments	0	0
Cash and cash equivalents	0	0
Recurring | NAV | Related Party
Assets
Other assets (related party: 2023 – $184 and 2022 – $161)		0
Recurring | NAV | Universal life
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | NAV | AmerUs Closed Block
Liabilities
Future policy benefits	0	0
Recurring | NAV | ILICO Closed Block and life benefits
Liabilities
Future policy benefits	0	0
Recurring | NAV | Embedded derivatives
Liabilities
Interest sensitive contract liabilities	0	0
Recurring | NAV | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Funds withheld at interest		0
Recurring | NAV | Embedded derivatives | Related Party
Assets
Funds withheld at interest		0
Recurring | NAV | U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | Corporate | Related Party
Assets
Available-for-sale securities	0	0
Recurring | NAV | CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | CLO | Related Party
Assets
Available-for-sale securities	0	0
Recurring | NAV | ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | ABS | Related Party
Assets
Available-for-sale securities	0	0
Recurring | NAV | CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Recurring | NAV | RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	0	0
Fair Value
Assets
Short-term investments		1,640
Total assets measured at fair value	40,541	51,798
Liabilities
Interest sensitive contract liabilities	126,779	111,608
Fair Value | Consolidated Entity, excluding Affiliated Entity
Assets
Investment funds	124	79
Funds withheld at interest	(30,934)	(37,727)
Other investments	45	162
Fair Value | Related Party
Assets
Investment funds	561	610
Funds withheld at interest	(7,592)	(11,233)
Short-term investments	949
Fair Value | Level 1
Assets
Short-term investments		0
Total assets measured at fair value	0	0
Liabilities
Interest sensitive contract liabilities	0	0
Fair Value | Level 1 | Consolidated Entity, excluding Affiliated Entity
Assets
Investment funds	0	0
Funds withheld at interest	0	0
Other investments	0	0
Fair Value | Level 1 | Related Party
Assets
Investment funds	0	0
Funds withheld at interest	0	0
Short-term investments	0
Fair Value | Level 2
Assets
Short-term investments		1,614
Total assets measured at fair value	1,285	1,961
Liabilities
Interest sensitive contract liabilities	0	0
Fair Value | Level 2 | Consolidated Entity, excluding Affiliated Entity
Assets
Investment funds	0	0
Funds withheld at interest	0	0
Other investments	0	0
Fair Value | Level 2 | Related Party
Assets
Investment funds	0	0
Funds withheld at interest	0	0
Short-term investments	949
Fair Value | Level 3
Assets
Short-term investments		26
Total assets measured at fair value	38,571	49,148
Liabilities
Interest sensitive contract liabilities	126,779	111,608
Fair Value | Level 3 | Consolidated Entity, excluding Affiliated Entity
Assets
Investment funds	0	0
Funds withheld at interest	(30,934)	(37,727)
Other investments	45	162
Fair Value | Level 3 | Related Party
Assets
Investment funds	0	0
Funds withheld at interest	(7,592)	(11,233)
Short-term investments	0
Fair Value | NAV
Assets
Total assets measured at fair value	685	689
Liabilities
Interest sensitive contract liabilities	0	0
Fair Value | NAV | Consolidated Entity, excluding Affiliated Entity
Assets
Investment funds	124	79
Funds withheld at interest	0	0
Short-term investments		0
Other investments	0	0
Fair Value | NAV | Related Party
Assets
Investment funds	561	610
Funds withheld at interest	0	0
Short-term investments	0
Fair Value | Recurring
Assets
Cash and cash equivalents	9,996	7,779
Restricted cash	1,218	628
Reinsurance recoverable	1,301	1,388
Other assets (related party: 2023 – $184 and 2022 – $161)	431
Total assets measured at fair value	206,330	170,587
Liabilities
Interest sensitive contract liabilities	8,084	6,670
Future policy benefits	1,651	1,712
Market risk benefits	3,021	2,970
Derivative liabilities	1,892	1,646
Other liabilities		65
Total liabilities measured at fair value	14,772	13,063
Fair Value | Recurring | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	115,715	102,404
Trading securities, at fair value	1,592	1,595
Equity securities, at fair value	916	1,087
Mortgage loans	37,978	27,454
Embedded derivative assets, fair value	(4,981)	(4,847)
Derivative assets	4,571	3,309
Short-term investments	527	520
Other investments	763	611
Fair Value | Recurring | Related Party
Assets
Available-for-sale securities	13,985	9,821
Trading securities, at fair value	871	878
Equity securities, at fair value	304	279
Mortgage loans	1,234	1,302
Investment funds	1,043	959
Embedded derivative assets, fair value	(972)	(1,425)
Other investments	327	303
Reinsurance recoverable		1,388
Fair Value | Recurring | Variable Interest Entities
Assets
Trading securities, at fair value	2,133	1,063
Mortgage loans	2,042	2,055
Investment funds	15,090	12,480
Other investments	94	101
Cash and cash equivalents	152	362
Fair Value | Recurring | Related Party
Assets
Other assets (related party: 2023 – $184 and 2022 – $161)		481
Fair Value | Recurring | Universal life
Liabilities
Interest sensitive contract liabilities	739	829
Fair Value | Recurring | AmerUs Closed Block
Liabilities
Future policy benefits	1,100	1,164
Fair Value | Recurring | ILICO Closed Block and life benefits
Liabilities
Future policy benefits	551	548
Fair Value | Recurring | Embedded derivatives
Liabilities
Interest sensitive contract liabilities	7,345	5,841
Fair Value | Recurring | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Funds withheld at interest		4,847
Fair Value | Recurring | Embedded derivatives | Related Party
Assets
Funds withheld at interest		(1,425)
Fair Value | Recurring | U.S. government and agencies | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	4,260	2,577
Fair Value | Recurring | US state, municipal and political subdivisions | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	962	927
Fair Value | Recurring | Foreign governments | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	915	907
Fair Value | Recurring | Corporate | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	67,301	60,901
Fair Value | Recurring | Corporate | Related Party
Assets
Available-for-sale securities	1,356	982
Fair Value | Recurring | CLO | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	18,926	16,493
Fair Value | Recurring | CLO | Related Party
Assets
Available-for-sale securities	4,235	3,079
Fair Value | Recurring | ABS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	10,807	10,527
Fair Value | Recurring | ABS | Related Party
Assets
Available-for-sale securities	8,394	5,760
Fair Value | Recurring | CMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	5,496	4,158
Fair Value | Recurring | RMBS | Consolidated Entity, excluding Affiliated Entity
Assets
Available-for-sale securities	7,048	$ 5,914
Funds withheld at interest | Recurring | Level 1
Liabilities
Other liabilities	0
Funds withheld at interest | Recurring | Level 1 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Recurring | Level 1 | Embedded derivatives | Related Party
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Recurring | Level 2 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Recurring | Level 2 | Embedded derivatives | Related Party
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Recurring | Level 3 | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Embedded derivative assets, fair value	(4,981)
Funds withheld at interest | Recurring | Level 3 | Embedded derivatives | Related Party
Assets
Embedded derivative assets, fair value	(972)
Funds withheld at interest | Recurring | NAV
Liabilities
Other liabilities	0
Funds withheld at interest | Recurring | NAV | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Recurring | NAV | Embedded derivatives | Related Party
Assets
Embedded derivative assets, fair value	0
Funds withheld at interest | Fair Value | Recurring
Liabilities
Other liabilities	124
Funds withheld at interest | Fair Value | Recurring | Embedded derivatives | Consolidated Entity, excluding Affiliated Entity
Assets
Embedded derivative assets, fair value	(4,981)
Funds withheld at interest | Fair Value | Recurring | Embedded derivatives | Related Party
Assets
Embedded derivative assets, fair value	$ (972)