FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost (Details) - USD ($) $ in Millions	Mar. 31, 2025		Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	$ 6,763		$ 5,958
Assets:
Amortized Cost	16,893		15,971
Fixed maturity securities, held-to-maturity, fair value	17,135		16,772
Commercial mortgage and other loans	10,656		10,869
Commercial mortgage and other loans, fair value	10,451		10,653
Other investments carried at amortized cost	37	[1]	39	[2]
Other investments carried at amortized cost, fair value	37	[1]	39	[2]
Total financial instruments assets not carried at fair value	27,581		26,874
Assets fair value disclosure financial instruments carried at cost	27,623		27,464
Liabilities:
Other policyholders’ funds	5,863		5,460
Other policyholders' funds fair value disclosure	5,789		5,389
Notes payable	7,653		7,402
Notes payable, fair value disclosure	7,247		7,027
Total financial instrument liabilities not carried at fair value	13,516		12,862
Liabilities fair value disclosure financial instruments carried at cost	13,036		12,416
Government and agencies
Assets:
Amortized Cost	16,193		15,309
Fixed maturity securities, held-to-maturity, fair value	16,406		16,059
Municipalities
Assets:
Amortized Cost	249		235
Fixed maturity securities, held-to-maturity, fair value	260		257
Public utilities
Assets:
Amortized Cost	33		32
Fixed maturity securities, held-to-maturity, fair value	33		33
Sovereign and supranational
Assets:
Amortized Cost	396		374
Fixed maturity securities, held-to-maturity, fair value	418		405
Other corporate
Assets:
Amortized Cost	17		16
Fixed maturity securities, held-to-maturity, fair value	18		18
Policy loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	211		203
Equity method investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	3,482		3,435
Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	774		682
Level 1
Assets:
Fixed maturity securities, held-to-maturity, fair value	16,262		15,916
Commercial mortgage and other loans, fair value	0		0
Other investments carried at amortized cost, fair value	0	[1]	0	[2]
Assets fair value disclosure financial instruments carried at cost	16,262		15,916
Liabilities:
Other policyholders' funds fair value disclosure	0		0
Notes payable, fair value disclosure	0		0
Liabilities fair value disclosure financial instruments carried at cost	0		0
Level 1 | Government and agencies
Assets:
Fixed maturity securities, held-to-maturity, fair value	16,262		15,916
Level 1 | Municipalities
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 1 | Public utilities
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 1 | Sovereign and supranational
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 1 | Other corporate
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 2
Assets:
Fixed maturity securities, held-to-maturity, fair value	873		856
Commercial mortgage and other loans, fair value	0		0
Other investments carried at amortized cost, fair value	37	[1]	39	[2]
Assets fair value disclosure financial instruments carried at cost	910		895
Liabilities:
Other policyholders' funds fair value disclosure	0		0
Notes payable, fair value disclosure	6,533		6,352
Liabilities fair value disclosure financial instruments carried at cost	6,533		6,352
Level 2 | Government and agencies
Assets:
Fixed maturity securities, held-to-maturity, fair value	144		143
Level 2 | Municipalities
Assets:
Fixed maturity securities, held-to-maturity, fair value	260		257
Level 2 | Public utilities
Assets:
Fixed maturity securities, held-to-maturity, fair value	33		33
Level 2 | Sovereign and supranational
Assets:
Fixed maturity securities, held-to-maturity, fair value	418		405
Level 2 | Other corporate
Assets:
Fixed maturity securities, held-to-maturity, fair value	18		18
Level 3
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Commercial mortgage and other loans, fair value	10,451		10,653
Other investments carried at amortized cost, fair value	0	[1]	0	[2]
Assets fair value disclosure financial instruments carried at cost	10,451		10,653
Liabilities:
Other policyholders' funds fair value disclosure	5,789		5,389
Notes payable, fair value disclosure	714		675
Liabilities fair value disclosure financial instruments carried at cost	6,503		6,064
Level 3 | Government and agencies
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 3 | Municipalities
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 3 | Public utilities
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 3 | Sovereign and supranational
Assets:
Fixed maturity securities, held-to-maturity, fair value	0		0
Level 3 | Other corporate
Assets:
Fixed maturity securities, held-to-maturity, fair value	$ 0		$ 0

[1] Excludes policy loans of $211, equity method investments of $3,482, and REO of $774, at carrying value

[2] Excludes policy loans of $203, equity method investments of $3,435, and REO of $682, at carrying value