FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Assets:
Available for sale, fixed maturity securities	$ 75,741	$ 98,696
Equity securities	1,091	1,603
Other investments	1,532	1,726
Cash and cash equivalents	3,943	5,051
Asset derivatives	$ 617	$ 936
Asset derivatives ext list	Other	Other
Total assets	$ 82,924	$ 108,012
Liabilities:
Liability derivatives	1,698	1,619
Total liabilities	1,698	1,619
Foreign currency swaps
Assets:
Asset derivatives	128	137
Liabilities:
Liability derivatives	390	427
Foreign currency forwards
Assets:
Asset derivatives	400	791
Liabilities:
Liability derivatives	725	1,138
Foreign currency options
Assets:
Asset derivatives	82	8
Interest rate swaps
Assets:
Asset derivatives	7
Liabilities:
Liability derivatives	583	54
Government and agencies
Assets:
Available for sale, fixed maturity securities	25,114	33,820
Municipalities
Assets:
Available for sale, fixed maturity securities	2,320	3,036
Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	2,146	1,246
Public utilities
Assets:
Available for sale, fixed maturity securities	7,666	10,051
Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	834	1,115
Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	9,299	11,591
Other corporate
Assets:
Available for sale, fixed maturity securities	28,362	37,837
Level 1
Assets:
Available for sale, fixed maturity securities	24,158	32,532
Equity securities	822	1,340
Other investments	1,532	1,726
Cash and cash equivalents	3,943	5,051
Asset derivatives	0	0
Total assets	30,455	40,649
Liabilities:
Total liabilities	0	0
Level 1 \| Foreign currency swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 \| Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 \| Foreign currency options
Assets:
Asset derivatives	0	0
Level 1 \| Interest rate swaps
Assets:
Asset derivatives	0
Liabilities:
Liability derivatives	0	0
Level 1 \| Government and agencies
Assets:
Available for sale, fixed maturity securities	24,158	32,532
Level 1 \| Municipalities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 \| Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 \| Public utilities
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 \| Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 \| Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	0	0
Level 1 \| Other corporate
Assets:
Available for sale, fixed maturity securities	0	0
Level 2
Assets:
Available for sale, fixed maturity securities	49,805	64,866
Equity securities	60	90
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	617	936
Total assets	50,482	65,892
Liabilities:
Total liabilities	1,698	1,619
Level 2 \| Foreign currency swaps
Assets:
Asset derivatives	128	137
Liabilities:
Liability derivatives	390	427
Level 2 \| Foreign currency forwards
Assets:
Asset derivatives	400	791
Liabilities:
Liability derivatives	725	1,138
Level 2 \| Foreign currency options
Assets:
Asset derivatives	82	8
Level 2 \| Interest rate swaps
Assets:
Asset derivatives	7
Liabilities:
Liability derivatives	583	54
Level 2 \| Government and agencies
Assets:
Available for sale, fixed maturity securities	956	1,288
Level 2 \| Municipalities
Assets:
Available for sale, fixed maturity securities	2,320	3,036
Level 2 \| Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	1,803	955
Level 2 \| Public utilities
Assets:
Available for sale, fixed maturity securities	7,169	9,558
Level 2 \| Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	797	1,072
Level 2 \| Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	9,140	11,546
Level 2 \| Other corporate
Assets:
Available for sale, fixed maturity securities	27,620	37,411
Level 3
Assets:
Available for sale, fixed maturity securities	1,778	1,298
Equity securities	209	173
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	0	0
Total assets	1,987	1,471
Liabilities:
Total liabilities	0	0
Level 3 \| Foreign currency swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 3 \| Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 3 \| Foreign currency options
Assets:
Asset derivatives	0	0
Level 3 \| Interest rate swaps
Assets:
Asset derivatives	0
Liabilities:
Liability derivatives	0	0
Level 3 \| Government and agencies
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 \| Municipalities
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 \| Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	343	291
Level 3 \| Public utilities
Assets:
Available for sale, fixed maturity securities	497	493
Level 3 \| Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	37	43
Level 3 \| Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	159	45
Level 3 \| Other corporate
Assets:
Available for sale, fixed maturity securities	$ 742	$ 426

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