FAIR VALUE MEASUREMENTS Fair Value Inputs Assets Quantitative Information (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014		Dec. 31, 2013
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	$ 67,318		$ 61,038
Asset derivatives	523		488
Assets, fair value	69,835		64,069
Length of Volatility of Japanese Yen to US Dollar Exchange Rate	10 years		10 years
Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	346		447
Asset derivatives	107		106
Assets, fair value	453		553
Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	64,281		58,070
Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	287		392
Perpetual securities:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3,016		2,947
Perpetual securities: | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	56		52
Equity Securities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	21		21
Equity Securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity Securities | Net Asset Value Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity Securities | Net Asset Value Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	3		3
Equity Securities | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$ 1		$ 1
Equity Securities | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$ 793		$ 774
Equity Securities | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Offered Quotes	$ 7		$ 7
Mortgage- and asset-backed Securities | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	666		771
Mortgage- and asset-backed Securities | Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	262		369
Mortgage- and asset-backed Securities | Fixed Maturities | Consensus Pricing Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	262		369
Mortgage- and asset-backed Securities | Fixed Maturities | Consensus Pricing Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	262		369
Banks/financial Institutions | Fixed Maturities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	6,792		6,509
Banks/financial Institutions | Fixed Maturities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	25		23
Banks/financial Institutions | Fixed Maturities | Consensus Pricing Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	25		23
Banks/financial Institutions | Fixed Maturities | Consensus Pricing Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	25		23
Banks/financial Institutions | Perpetual securities:
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	2,787		2,738
Banks/financial Institutions | Perpetual securities: | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	56		52
Banks/financial Institutions | Perpetual securities: | Consensus Pricing Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities			52
Banks/financial Institutions | Perpetual securities: | Model Pricing Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Available-for-sale Securities	56
Interest rate swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Interest rate swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Interest rate swaps | Discounted Cash Flow Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives			1
Interest rate swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			65.00%	[1]
Fair Value Inputs, Entity Credit Risk			0.65%
Interest rate swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			76.00%	[1]
Fair Value Inputs, Entity Credit Risk			1.06%
Interest rate swaps | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			72.00%	[1]
Fair Value Inputs, Entity Credit Risk			0.92%
Fair Value Inputs, Recovery Rate			37.00%
Foreign currency swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	426		445
Foreign currency swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	106		104
Credit default swaps
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	1		1
Credit default swaps | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	1		1
Credit default swaps | Discounted Cash Flow Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	1		1
Credit default swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation	65.00%	[1]	65.00%	[1]
Fair Value Inputs, Entity Credit Risk	0.66%		0.65%
Credit default swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation	75.00%	[1]	76.00%	[1]
Fair Value Inputs, Entity Credit Risk	1.01%		1.06%
Credit default swaps | Assets | Weighted Average | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation	72.00%	[1]	72.00%	[1]
Fair Value Inputs, Entity Credit Risk	0.86%		0.92%
Fair Value Inputs, Recovery Rate	37.00%		37.00%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Discounted Cash Flow Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	30		30
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.45%	[2]	21.16%	[2]
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.11%		0.16%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.24%		1.41%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Discounted Cash Flow Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	8		9
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.21%		0.17%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.20%		1.49%
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Discounted Cash Flow Valuation Technique | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Asset derivatives	$ 68		$ 65
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.45%	[2]	21.16%	[2]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.83%	[3]	0.93%	[3]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.96%	[3]	2.02%	[3]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.83%	[3]	0.93%	[3]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.96%	[3]	2.02%	[3]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.83%	[3]	0.93%	[3]
Japan, Yen | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.96%	[3]	2.02%	[3]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.84%	[4]	3.09%	[4]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	3.56%	[4]	3.96%	[4]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.84%	[4]	3.09%	[4]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spread | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	3.56%	[4]	3.96%	[4]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Lower Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.84%	[4]	3.09%	[4]
United States of America, Dollars | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Assets | Upper Limit | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	3.56%	[4]	3.96%	[4]

[1] Weighted-average range of base correlations for our bespoke tranches for attachment and detachment points corresponding to market indices

[2] Based on 10 year volatility of JPY/USD exchange rate

[3] Inputs derived from Japan long-term rates to accommodate long maturity nature of our swaps

[4] Inputs derived from U.S. long-term rates to accommodate long maturity nature of our swaps