FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 4) (USD $) In Thousands, except Per Share data, unless otherwise specified			12 Months Ended				12 Months Ended							12 Months Ended			12 Months Ended							12 Months Ended					12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Minimum	Dec. 31, 2012 Maximum	Dec. 31, 2012 Market comparables Level 3 - Total Common Stock Warrants Weighted Average	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Yield Analysis Weighted Average	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Yield Analysis Minimum	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Yield Analysis Maximum	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Broker quotes Weighted Average	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Broker quotes Minimum	Dec. 31, 2012 Level 3 - Total Securities Available-For-Sale: Corporate Debt Securities Broker quotes Maximum	Dec. 31, 2012 Level 3 - Total Other Securities, at Estimated Fair Value	Dec. 31, 2012 Level 3 - Total Other Securities, at Estimated Fair Value Yield Analysis Weighted Average	Dec. 31, 2012 Level 3 - Total Residential Mortgage-Backed Securities	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Yield Analysis Weighted Average	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Yield Analysis Minimum	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Yield Analysis Maximum	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Broker quotes Weighted Average	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Broker quotes Minimum	Dec. 31, 2012 Level 3 - Total Corporate Loans, at Estimated Fair Value Broker quotes Maximum	Dec. 31, 2012 Level 3 - Total Equity investments, at Estimated Fair Value	Dec. 31, 2012 Level 3 - Total Equity investments, at Estimated Fair Value Minimum	Dec. 31, 2012 Level 3 - Total Equity investments, at Estimated Fair Value Market comparables Weighted Average	Dec. 31, 2012 Level 3 - Total Equity investments, at Estimated Fair Value Market comparables Minimum	Dec. 31, 2012 Level 3 - Total Equity investments, at Estimated Fair Value Market comparables Maximum	Dec. 31, 2012 Level 3 - Total Interests in joint ventures and partnerships	Dec. 31, 2012 Discounted cash flow Level 3 - Total Common Stock Warrants Weighted Average	Dec. 31, 2012 Discounted cash flow Level 3 - Total Residential Mortgage-Backed Securities Weighted Average	Dec. 31, 2012 Discounted cash flow Level 3 - Total Residential Mortgage-Backed Securities Minimum	Dec. 31, 2012 Discounted cash flow Level 3 - Total Residential Mortgage-Backed Securities Maximum	Dec. 31, 2012 Discounted cash flow Level 3 - Total Equity investments, at Estimated Fair Value Weighted Average	Dec. 31, 2012 Discounted cash flow Level 3 - Total Equity investments, at Estimated Fair Value Minimum	Dec. 31, 2012 Discounted cash flow Level 3 - Total Equity investments, at Estimated Fair Value Maximum	Dec. 31, 2012 Discounted cash flow Level 3 - Total Interests in joint ventures and partnerships Weighted Average	Dec. 31, 2012 Discounted cash flow Level 3 - Total Interests in joint ventures and partnerships Minimum	Dec. 31, 2012 Discounted cash flow Level 3 - Total Interests in joint ventures and partnerships Maximum	Dec. 31, 2012 Option pricing model Level 3 - Total Foreign Exchange Options - Assets Weighted Average	Dec. 31, 2012 Option pricing model Level 3 - Total Foreign Exchange Options - Assets Minimum	Dec. 31, 2012 Option pricing model Level 3 - Total Foreign Exchange Options - Assets Maximum
Valuation techniques used for assets, measured at fair value and categarized within level 3
Securities available-for-sale	$ 412,293	$ 816,453				$ 42,221
Other securities, at estimated fair value													2,909
Residential mortgage-backed securities															83,842
Corporate loans, at estimated fair value																16,141
Equity investments, at estimated fair value	161,621	189,845																					97,746
Derivative asset, fair value																												$ 142,477
Yield							16.00%	11.00%	46.00%					10.00%
Discount margin							14.50%	11.00%	45.50%
Net leverage							6	3	13								9	8	9
Illiquidity discount					15.00%		3.00%		3.00%								15.00%							5.00%												10.00%	10.00%	15.00%
EBITDA multiple							7	6	8								10	9	10
Offered quotes										$ 88	$ 69	$ 105								$ 39	$ 8	$ 40
Probability of default																														6.00%	0.00%	21.00%
Loss severity																														30.00%	18.00%	80.00%
Constant prepayment rate																														13.00%	1.00%	35.00%
LTM EBITDA multiple					7																				10	7	12
Forward EBITDA multiple					7																				10	6	12
Control premium																									0.00%
Weighted average cost of capital																													12.00%				10.00%	6.00%	16.00%	18.00%	13.00%	30.00%
LTM EBITDA exit multiple																													7				9	7	12
Forward and spot rates, Assets																																							0.01	0.00	0.02
Weight ascribed to each valuation technique (as a percent)			0.00%	100.00%