FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Assets:
Available for sale, fixed maturity securities	$ 93,940	$ 82,895
Equity securities	830	987
Other investments	722	152
Cash and cash equivalents	4,216	4,337
Asset derivatives	411	417
Total assets	100,119	88,788
Liabilities:
Liability derivatives	403	387
Total liabilities	403	387
Foreign currency swaps
Assets:
Asset derivatives	227	285
Liabilities:
Liability derivatives	227	234
Foreign currency forwards
Assets:
Asset derivatives	170	126
Liabilities:
Liability derivatives	168	151
Foreign currency options
Assets:
Asset derivatives	1	3
Liabilities:
Liability derivatives	8	1
Interest rate swaps
Assets:
Asset derivatives	13	3
Interest rate swaptions
Liabilities:
Liability derivatives		1
Government and agencies
Assets:
Available for sale, fixed maturity securities	38,296	34,342
Municipalities
Assets:
Available for sale, fixed maturity securities	1,898	1,863
Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	409	339
Public utilities
Assets:
Available for sale, fixed maturity securities	6,950	7,171
Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	1,084	1,260
Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	10,644	8,918
Other corporate
Assets:
Available for sale, fixed maturity securities	34,659	29,002
Level 1
Assets:
Available for sale, fixed maturity securities	36,705	32,993
Equity securities	677	874
Other investments	722	152
Cash and cash equivalents	4,216	4,337
Asset derivatives	0	0
Total assets	42,320	38,356
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
Liabilities:
Liability derivatives	0	0
Level 1 \| Interest rate swaps
Assets:
Asset derivatives	0	0
Level 1 \| Interest rate swaptions
Liabilities:
Liability derivatives		0
Level 1 \| Government and agencies
Assets:
Available for sale, fixed maturity securities	36,705	32,993
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	56,599	49,380
Equity securities	74	67
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	264	235
Total assets	56,937	49,682
Liabilities:
Total liabilities	264	285
Level 2 \| Foreign currency swaps
Assets:
Asset derivatives	80	103
Liabilities:
Liability derivatives	88	132
Level 2 \| Foreign currency forwards
Assets:
Asset derivatives	170	126
Liabilities:
Liability derivatives	168	151
Level 2 \| Foreign currency options
Assets:
Asset derivatives	1	3
Liabilities:
Liability derivatives	8	1
Level 2 \| Interest rate swaps
Assets:
Asset derivatives	13	3
Level 2 \| Interest rate swaptions
Liabilities:
Liability derivatives		1
Level 2 \| Government and agencies
Assets:
Available for sale, fixed maturity securities	1,591	1,349
Level 2 \| Municipalities
Assets:
Available for sale, fixed maturity securities	1,898	1,863
Level 2 \| Mortgage- and asset-backed securities
Assets:
Available for sale, fixed maturity securities	226	162
Level 2 \| Public utilities
Assets:
Available for sale, fixed maturity securities	6,744	7,062
Level 2 \| Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	1,084	1,260
Level 2 \| Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	10,621	8,895
Level 2 \| Other corporate
Assets:
Available for sale, fixed maturity securities	34,435	28,789
Level 3
Assets:
Available for sale, fixed maturity securities	636	522
Equity securities	79	46
Other investments	0	0
Cash and cash equivalents	0	0
Asset derivatives	147	182
Total assets	862	750
Liabilities:
Total liabilities	139	102
Level 3 \| Foreign currency swaps
Assets:
Asset derivatives	147	182
Liabilities:
Liability derivatives	139	102
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
Liabilities:
Liability derivatives	0	0
Level 3 \| Interest rate swaps
Assets:
Asset derivatives	0	0
Level 3 \| Interest rate swaptions
Liabilities:
Liability derivatives		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	183	177
Level 3 \| Public utilities
Assets:
Available for sale, fixed maturity securities	206	109
Level 3 \| Sovereign and supranational
Assets:
Available for sale, fixed maturity securities	0	0
Level 3 \| Banks/financial institutions
Assets:
Available for sale, fixed maturity securities	23	23
Level 3 \| Other corporate
Assets:
Available for sale, fixed maturity securities	$ 224	$ 213

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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