FAIR VALUE MEASUREMENTS - Fair Value Inputs Liabilities Quantitative Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	$ 2,423		$ 837
Liabilities, fair value disclosure	2,423		837
Length of Volatility of Japanese Yen to US Dollar Exchange Rate	10 years		10 years
Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liabilities, fair value disclosure	318		207
Foreign currency swaps
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	318		218
Foreign currency swaps | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	318		203
Credit default swaps
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			4
Credit default swaps | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			4
Credit default swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			65.00%	[1]
Fair Value Inputs, Entity Credit Risk			0.65%
Credit default swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Base Correlation			76.00%	[1]
Fair Value Inputs, Entity Credit Risk			1.06%
Credit default swaps | Liability | Weighted Average | Level 3
Fair Value Inputs, Liabilities, 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%
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, Liabilities, Quantitative Information [Line Items]
Liability derivatives	176		99
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.16%		0.16%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.05%		1.41%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives	111		24
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	0.13%		0.11%
Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.45%		1.89%
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, Liabilities, Quantitative Information [Line Items]
Liability derivatives	31		80
Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Foreign Exchange Rates	20.50%	[2]	21.16%	[2]
Fair value, unobservable input, base correlation, CDS spreads, recovery rate | Credit default swaps | Discounted cash flow valuation technique | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Liability derivatives			$ 4
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.53%	[3]	0.93%	[3]
Yen-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.34%	[3]	2.02%	[3]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), CDS Spreads and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[4]	3.96%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Lower Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.28%	[4]	3.09%	[4]
Dollar-denominated | Fair Value, Unobservable Input, Interest Rates (USD), interest rates (JPY), and Foreign Exchange Rates | Foreign currency swaps | Liability | Upper Limit | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	2.70%	[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