INVESTMENTS - Available-For-Sale Investments in Debt Securities, Perpetual Securities and Equity Securities (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$ 59,515	$ 57,646
Gross Unrealized Gains	3,659	4,716
Gross Unrealized Losses	2,136	784
Fair Value	61,038	61,578
Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	56,511	53,413
Gross Unrealized Gains	3,468	4,453
Gross Unrealized Losses	1,909	613
Fair Value	58,070	57,253
Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,987	4,213
Gross Unrealized Gains	186	259
Gross Unrealized Losses	226	170
Fair Value	2,947	4,302
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	17	20
Gross Unrealized Gains	5	4
Gross Unrealized Losses	1	1
Fair Value	21	23
Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	25,488	27,481
Gross Unrealized Gains	1,016	1,050
Gross Unrealized Losses	506	487
Fair Value	25,998	28,044
Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	31,023	25,932
Gross Unrealized Gains	2,452	3,403
Gross Unrealized Losses	1,403	126
Fair Value	32,072	29,209
Japan government and agencies | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	14,936	12,612
Gross Unrealized Gains	431	349
Gross Unrealized Losses	33	81
Fair Value	15,334	12,880
Mortgage- and asset-backed Securities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	771	1,031
Mortgage- and asset-backed Securities | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	558	746
Gross Unrealized Gains	29	40
Gross Unrealized Losses	0	1
Fair Value	587	785
Mortgage- and asset-backed Securities | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	163	188
Gross Unrealized Gains	21	58
Gross Unrealized Losses	0	0
Fair Value	184	246
Public Utilities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	7,562	8,497
Public Utilities | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,261	3,608
Gross Unrealized Gains	100	116
Gross Unrealized Losses	18	72
Fair Value	2,343	3,652
Public Utilities | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	4,931	4,204
Gross Unrealized Gains	471	658
Gross Unrealized Losses	183	17
Fair Value	5,219	4,845
Sovereign and Supranational | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	1,523	2,072
Sovereign and Supranational | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	978	1,404
Gross Unrealized Gains	85	71
Gross Unrealized Losses	28	0
Fair Value	1,035	1,475
Sovereign and Supranational | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	404	476
Gross Unrealized Gains	85	123
Gross Unrealized Losses	1	2
Fair Value	488	597
Banks/financial Institutions | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	6,509	7,634
Banks/financial Institutions | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	2,738	3,950
Banks/financial Institutions | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,799	3,455
Gross Unrealized Gains	220	233
Gross Unrealized Losses	242	180
Fair Value	2,777	3,508
Banks/financial Institutions | Yen Denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,582	3,635
Gross Unrealized Gains	151	193
Gross Unrealized Losses	217	161
Fair Value	2,516	3,667
Banks/financial Institutions | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,318	3,626
Gross Unrealized Gains	447	506
Gross Unrealized Losses	33	6
Fair Value	3,732	4,126
Banks/financial Institutions | Dollar Denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	196	269
Gross Unrealized Gains	35	23
Gross Unrealized Losses	9	9
Fair Value	222	283
Other Corporate | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	25,222	23,827
Other Corporate | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	209	352
Other Corporate | Yen Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,956	5,656
Gross Unrealized Gains	151	241
Gross Unrealized Losses	185	153
Fair Value	3,922	5,744
Other Corporate | Yen Denominated | Perpetual securities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	209	309
Gross Unrealized Gains	0	43
Gross Unrealized Losses	0	0
Fair Value	209	352
Other Corporate | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	21,123	16,300
Gross Unrealized Gains	1,347	1,878
Gross Unrealized Losses	1,170	95
Fair Value	21,300	18,083
U.S. Government and Agencies | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	92	93
Gross Unrealized Gains	10	24
Gross Unrealized Losses	4	0
Fair Value	98	117
Municipalities | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	1,051	1,195
Municipalities | Dollar Denominated | Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	992	1,045
Gross Unrealized Gains	71	156
Gross Unrealized Losses	12	6
Fair Value	$ 1,051	$ 1,195