Valuation (Schedule Of Significant Unobservable Inputs, Qualitative Information) (Details) - Level 3 [Member]	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($)		Dec. 31, 2015 USD ($)
Market Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 75,404,000		$ 89,549,000
Market Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	1.88		1.81
Market Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	153.12		151.86
Market Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	66.93		68.47
Market Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 25,830,000		$ 41,978,000
Market Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	27.00		13.00
Market Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	101.50		102.00
Market Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	83.73		84.84
Market Approach Valuation Technique [Member] | Corporate Debt and non-exchange traded corporate equity [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 20,784,000		$ 18,972,000
Market Approach Valuation Technique [Member] | Corporate Debt and non-exchange traded corporate equity [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	2.83		3.00
Market Approach Valuation Technique [Member] | Corporate Debt and non-exchange traded corporate equity [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	200.00		200.00
Market Approach Valuation Technique [Member] | Corporate Debt and non-exchange traded corporate equity [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	70.37		77.85
Market Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 16,161,000		$ 20,365,000
Market Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	5.05		6.07
Market Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	67.29		73.20
Market Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	32.16		41.28
Market Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 18,628,000		$ 21,067,000
Market Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	2.77		2.97
Market Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	24.75		22.41
Market Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	10.61		11.08
Income Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 37,978,000		$ 26,886,000
Income Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	4.40%		3.40%
Projected Collateral Prepayments	4.90%		5.40%
Fair Value Inputs Losses	4.40%		2.90%
Fair Value Inputs Projected Collateral Recoveries	0.00%		0.30%
Fair Value Inputs Projected Collateral Scheduled Amortization	7.90%		8.60%
Income Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	13.00%		27.10%
Projected Collateral Prepayments	75.60%		74.60%
Fair Value Inputs Losses	25.60%		24.50%
Fair Value Inputs Projected Collateral Recoveries	12.10%		13.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	88.80%		88.60%
Income Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	11.60%		19.90%
Projected Collateral Prepayments	36.90%		46.30%
Fair Value Inputs Losses	12.90%		11.40%
Fair Value Inputs Projected Collateral Recoveries	5.60%		8.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	44.60%		34.30%
Total Outstanding Collateral	100.00%		100.00%
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 8,585,000		$ 3,996,000
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	10.50%		8.30%
Projected Collateral Prepayments	30.90%		31.90%
Fair Value Inputs Losses	1.40%		2.60%
Fair Value Inputs Projected Collateral Recoveries	1.50%		2.30%
Fair Value Inputs Projected Collateral Scheduled Amortization	26.40%		33.30%
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	66.50%		20.60%
Projected Collateral Prepayments	67.60%		52.30%
Fair Value Inputs Losses	19.20%		17.30%
Fair Value Inputs Projected Collateral Recoveries	16.50%		15.50%
Fair Value Inputs Projected Collateral Scheduled Amortization	53.60%		51.50%
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	18.80%		13.50%
Projected Collateral Prepayments	51.00%		41.10%
Fair Value Inputs Losses	7.10%		12.90%
Fair Value Inputs Projected Collateral Recoveries	5.40%		10.10%
Fair Value Inputs Projected Collateral Scheduled Amortization	36.50%		35.90%
Total Outstanding Collateral	100.00%		100.00%
Income Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 19,189,000		$ 13,780,000
Income Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	11.60%		19.20%
Fair Value Inputs Losses	0.60%		0.70%
Fair Value Inputs Projected Collateral Recoveries	2.10%		1.50%
Fair Value Inputs Projected Collateral Scheduled Amortization	87.90%		83.40%
Income Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	32.80%		25.00%
Fair Value Inputs Losses	2.40%		2.30%
Fair Value Inputs Projected Collateral Recoveries	11.10%		14.30%
Fair Value Inputs Projected Collateral Scheduled Amortization	97.30%		97.60%
Income Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	21.20%		22.10%
Fair Value Inputs Losses	1.20%		1.60%
Fair Value Inputs Projected Collateral Recoveries	5.40%		8.40%
Fair Value Inputs Projected Collateral Scheduled Amortization	93.40%		90.00%
Total Outstanding Collateral	100.00%		100.00%
Income Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 3,678,000		$ 3,851,000
Income Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	20.30%		18.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	0.00%		0.00%
LIBOR OAS	4.41%	[1]	4.41%	[2]
Income Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	100.00%		100.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	79.70%		82.00%
LIBOR OAS	18.07%	[1]	16.72%	[2]
Income Approach Valuation Technique [Member] | Agency Interest Only Residential Mortgage-Backed Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	64.10%		70.40%
Fair Value Inputs Projected Collateral Scheduled Amortization	35.90%		29.60%
Total Outstanding Collateral	100.00%		100.00%
LIBOR OAS	7.01%	[1]	6.22%	[2]
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 10,450,000		$ 13,920,000
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	0.00%		15.00%
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	15.30%		20.00%
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	14.80%		16.20%
Income Approach Valuation Technique [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 143,854,000		$ 115,376,000
Income Approach Valuation Technique [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	9.00%		9.00%
Projected Collateral Prepayments	0.00%		0.00%
Fair Value Inputs Losses	1.00%		1.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	56.10%		57.30%
Income Approach Valuation Technique [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	25.00%		15.00%
Projected Collateral Prepayments	42.10%		40.90%
Fair Value Inputs Losses	33.80%		33.80%
Fair Value Inputs Projected Collateral Scheduled Amortization	80.70%		80.80%
Income Approach Valuation Technique [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	10.30%		10.40%
Projected Collateral Prepayments	31.60%		30.90%
Fair Value Inputs Losses	7.60%		7.30%
Fair Value Inputs Projected Collateral Scheduled Amortization	60.80%		61.80%
Total Outstanding Collateral	100.00%		100.00%
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 30,189,000		$ 43,847,000
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	10.40%		9.80%
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	17.60%		17.60%
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	11.70%		11.90%
Income Approach Valuation Technique [Member] | Non-performing Commercial Mortgage Loans and commercial real estate owned [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 24,707,000		$ 30,984,000
Income Approach Valuation Technique [Member] | Non-performing Commercial Mortgage Loans and commercial real estate owned [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	10.20%		10.20%
Months to Resolution	3 months		4 months
Income Approach Valuation Technique [Member] | Non-performing Commercial Mortgage Loans and commercial real estate owned [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	28.30%		19.40%
Months to Resolution	39 months 24 days		24 months
Income Approach Valuation Technique [Member] | Non-performing Commercial Mortgage Loans and commercial real estate owned [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	15.50%		13.70%
Months to Resolution	18 months 21 days		9 months 10 days
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 28,877,000		$ 13,848,000
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	5.40%		5.50%
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	11.10%		8.00%
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	6.60%		6.50%
Income Approach Valuation Technique [Member] | Non-performing Residential Mortgage Loans and Residential Real Estate Owned [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 9,482,000		$ 12,331,000
Income Approach Valuation Technique [Member] | Non-performing Residential Mortgage Loans and Residential Real Estate Owned [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	6.50%		5.70%
Months to Resolution	3 months 12 days		3 months 12 days
Income Approach Valuation Technique [Member] | Non-performing Residential Mortgage Loans and Residential Real Estate Owned [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	11.40%		7.90%
Months to Resolution	120 months 6 days		113 months 18 days
Income Approach Valuation Technique [Member] | Non-performing Residential Mortgage Loans and Residential Real Estate Owned [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	8.70%		7.30%
Months to Resolution	24 months 24 days		20 months 18 days
Recent Transactions [Member] | Commercial Mortgage Loans and REO [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 20,533,000
Recent Transactions [Member] | Commercial Mortgage Loans and REO [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Contract Price	44.29
Recent Transactions [Member] | Commercial Mortgage Loans and REO [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Contract Price	95.08
Recent Transactions [Member] | Commercial Mortgage Loans and REO [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Contract Price	64.25
Credit Default Swaps On Asset Backed Securities [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 6,007,000		$ 6,111,000
Credit Default Swaps On Asset Backed Securities [Member] | Income Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	27.20%		26.60%
Fair Value Inputs Losses	15.70%		15.00%
Fair Value Inputs Projected Collateral Recoveries	6.40%		6.80%
Fair Value Inputs Projected Collateral Scheduled Amortization	23.10%		24.50%
Credit Default Swaps On Asset Backed Securities [Member] | Income Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	50.30%		44.10%
Fair Value Inputs Losses	34.80%		33.70%
Fair Value Inputs Projected Collateral Recoveries	15.00%		16.90%
Fair Value Inputs Projected Collateral Scheduled Amortization	32.00%		33.10%
Credit Default Swaps On Asset Backed Securities [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Projected Collateral Prepayments	33.40%		32.60%
Fair Value Inputs Losses	28.00%		26.50%
Fair Value Inputs Projected Collateral Recoveries	10.60%		12.00%
Fair Value Inputs Projected Collateral Scheduled Amortization	28.00%		28.90%
Total Outstanding Collateral	100.00%		100.00%
Total Return Swaps [Member] | Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 399,000
Financial and Nonfinancial Liabilities, Fair Value Disclosure			$ (4,577,000)
Total Return Swaps [Member] | Market Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	16.31	[3]	36.38	[4]
Total Return Swaps [Member] | Market Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	100.38	[3]	99.88	[4]
Total Return Swaps [Member] | Market Approach Valuation Technique [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Non Binding Third-Party Valuation	94.29	[3]	56.38	[4]
Guarantees [Member] | Recent Transactions [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ (616,000)		$ (828,000)
Private Corporate Equity Investments [Member] | Non-exchange traded equity investments in commercial mortgage-related private partnerships [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 10,435,000		$ 10,558,000
Private Corporate Equity Investments [Member] | Non-exchange traded equity investments in commercial mortgage-related private partnerships [Member] | Income Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	15.60%		14.00%
Expected Holding Period (Months)	11 months 15 days		14 months 9 days
Private Corporate Equity Investments [Member] | Non-exchange traded equity investments in commercial mortgage-related private partnerships [Member] | Income Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	16.50%		16.50%
Expected Holding Period (Months)	24 months 15 days		27 months
Private Corporate Equity Investments [Member] | Non-exchange traded equity investments in commercial mortgage-related private partnerships [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield	15.90%		14.70%
Expected Holding Period (Months)	20 months 24 days		23 months 15 days
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred and Common Equity Investment in Mortgage-Related Entities [Member] | Enterprise Value [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 2,053,000		$ 2,738,000
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred and Common Equity Investment in Mortgage-Related Entities [Member] | Enterprise Value [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Multiple	1.9	[5]	2.7	[6]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred and Common Equity Investment in Mortgage-Related Entities [Member] | Enterprise Value [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Multiple	1.9	[5]	2.7	[6]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred and Common Equity Investment in Mortgage-Related Entities [Member] | Enterprise Value [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Multiple	1.9	[5]	2.7	[6]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred and Common Equity Investment in Mortgage-Related Entities [Member] | Recent Transactions [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 2,500,000		$ 2,630,000

[1] Shown in basis points.

[2] Shown in basis points.

[3] Represents valuations on underlying assets.

[4] Represents valuations on underlying assets.

[5] Represent an estimation of where market participants might value an enterprise.

[6] Represent an estimation of where market participants might value an enterprise.