FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Assets:
Available-for-sale Securities	$ 67,318	$ 61,038
Asset derivatives	523	488
Cash and cash equivalents	1,994	2,543
Total assets	69,835	64,069
Liabilities:
Liability derivatives	358	837
Total liabilities	358	837
Foreign currency swaps
Assets:
Asset derivatives	426	445
Liabilities:
Liability derivatives	206	218
Foreign currency forwards
Assets:
Asset derivatives	58	17
Liabilities:
Liability derivatives	59	582
Foreign currency options
Assets:
Asset derivatives	26	4
Liabilities:
Liability derivatives	23	1
Credit default swaps
Assets:
Asset derivatives	1	1
Liabilities:
Liability derivatives	2	4
Interest rate swaps
Assets:
Asset derivatives		1
Interest rate swaptions
Assets:
Asset derivatives	12	20
Liabilities:
Liability derivatives	61	32
Futures
Liabilities:
Liability derivatives	7
Fixed Maturities
Assets:
Available-for-sale Securities	64,281	58,070
Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	18,906	15,432
Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,097	1,051
Fixed Maturities | Mortgage- and asset-backed Securities
Assets:
Available-for-sale Securities	666	771
Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	7,926	7,562
Fixed Maturities | Sovereign and Supranational
Assets:
Available-for-sale Securities	1,544	1,523
Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,792	6,509
Fixed Maturities | Other Corporate
Assets:
Available-for-sale Securities	27,350	25,222
Perpetual securities:
Assets:
Available-for-sale Securities	3,016	2,947
Perpetual securities: | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,787	2,738
Perpetual securities: | Other Corporate
Assets:
Available-for-sale Securities	229	209
Equity Securities
Assets:
Available-for-sale Securities	21	21
Level 1
Assets:
Available-for-sale Securities	18,421	14,942
Asset derivatives	0	0
Cash and cash equivalents	1,994	2,543
Total assets	20,415	17,485
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 | Credit default swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Interest rate swaps
Assets:
Asset derivatives		0
Level 1 | Interest rate swaptions
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Futures
Liabilities:
Liability derivatives	0
Level 1 | Fixed Maturities
Assets:
Available-for-sale Securities	18,407	14,928
Level 1 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	18,407	14,928
Level 1 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Mortgage- and asset-backed Securities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Sovereign and Supranational
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Other Corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities:
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities: | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities: | Other Corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Equity Securities
Assets:
Available-for-sale Securities	14	14
Level 2
Assets:
Available-for-sale Securities	48,551	45,649
Asset derivatives	416	382
Cash and cash equivalents	0	0
Total assets	48,967	46,031
Liabilities:
Total liabilities	164	630
Level 2 | Foreign currency swaps
Assets:
Asset derivatives	320	341
Liabilities:
Liability derivatives	14	15
Level 2 | Foreign currency forwards
Assets:
Asset derivatives	58	17
Liabilities:
Liability derivatives	59	582
Level 2 | Foreign currency options
Assets:
Asset derivatives	26	4
Liabilities:
Liability derivatives	23	1
Level 2 | Credit default swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 2 | Interest rate swaps
Assets:
Asset derivatives		0
Level 2 | Interest rate swaptions
Assets:
Asset derivatives	12	20
Liabilities:
Liability derivatives	61	32
Level 2 | Futures
Liabilities:
Liability derivatives	7
Level 2 | Fixed Maturities
Assets:
Available-for-sale Securities	45,587	42,750
Level 2 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	499	504
Level 2 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,097	1,051
Level 2 | Fixed Maturities | Mortgage- and asset-backed Securities
Assets:
Available-for-sale Securities	404	402
Level 2 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	7,926	7,562
Level 2 | Fixed Maturities | Sovereign and Supranational
Assets:
Available-for-sale Securities	1,544	1,523
Level 2 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,767	6,486
Level 2 | Fixed Maturities | Other Corporate
Assets:
Available-for-sale Securities	27,350	25,222
Level 2 | Perpetual securities:
Assets:
Available-for-sale Securities	2,960	2,895
Level 2 | Perpetual securities: | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,731	2,686
Level 2 | Perpetual securities: | Other Corporate
Assets:
Available-for-sale Securities	229	209
Level 2 | Equity Securities
Assets:
Available-for-sale Securities	4	4
Level 3
Assets:
Available-for-sale Securities	346	447
Asset derivatives	107	106
Cash and cash equivalents	0	0
Total assets	453	553
Liabilities:
Total liabilities	194	207
Level 3 | Foreign currency swaps
Assets:
Asset derivatives	106	104
Liabilities:
Liability derivatives	192	203
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 | Credit default swaps
Assets:
Asset derivatives	1	1
Liabilities:
Liability derivatives	2	4
Level 3 | Interest rate swaps
Assets:
Asset derivatives		1
Level 3 | Interest rate swaptions
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 3 | Futures
Liabilities:
Liability derivatives	0
Level 3 | Fixed Maturities
Assets:
Available-for-sale Securities	287	392
Level 3 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Mortgage- and asset-backed Securities
Assets:
Available-for-sale Securities	262	369
Level 3 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Sovereign and Supranational
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	25	23
Level 3 | Fixed Maturities | Other Corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Perpetual securities:
Assets:
Available-for-sale Securities	56	52
Level 3 | Perpetual securities: | Banks/financial Institutions
Assets:
Available-for-sale Securities	56	52
Level 3 | Perpetual securities: | Other Corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Equity Securities
Assets:
Available-for-sale Securities	$ 3	$ 3