Valuation (Schedule Of Significant Unobservable Inputs, Qualitative Information) (Details) - Level 3 [Member]		9 Months Ended		12 Months Ended
		Sep. 30, 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		$ 51,029,000		$ 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		2.17		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		116.28		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		69.15		68.47
Market Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 24,292,000		$ 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		12.25		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		434.04		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		85.10		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		$ 11,928,000		$ 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		0.40		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		115.25		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		94.79		77.85
Market Approach Valuation Technique [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 18,636,000		$ 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		4.84		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		70.52		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		34.36		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		$ 18,131,000		$ 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		2.58		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		22.52		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		10.67		11.08
Income Approach Valuation Technique [Member] | Private Label Residential Mortgage Backed Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 30,916,000		$ 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		2.00%		3.40%
Projected Collateral Prepayments		0.00%		5.40%
Fair Value Inputs Losses		2.70%		2.90%
Fair Value Inputs Projected Collateral Recoveries		0.00%		0.30%
Fair Value Inputs Projected Collateral Scheduled Amortization		0.00%		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		21.50%		27.10%
Projected Collateral Prepayments		75.40%		74.60%
Fair Value Inputs Losses		50.80%		24.50%
Fair Value Inputs Projected Collateral Recoveries		52.60%		13.00%
Fair Value Inputs Projected Collateral Scheduled Amortization		62.50%		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		10.60%		19.90%
Projected Collateral Prepayments		10.60%		46.30%
Fair Value Inputs Losses		40.70%		11.40%
Fair Value Inputs Projected Collateral Recoveries		41.80%		8.00%
Fair Value Inputs Projected Collateral Scheduled Amortization		6.90%		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		$ 4,111,000		$ 3,996,000
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		14.60%		8.30%
Projected Collateral Prepayments		27.90%		31.90%
Fair Value Inputs Losses		5.80%		2.60%
Fair Value Inputs Projected Collateral Recoveries		1.50%		2.30%
Fair Value Inputs Projected Collateral Scheduled Amortization		28.50%		33.30%
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		35.10%		20.60%
Projected Collateral Prepayments		60.00%		52.30%
Fair Value Inputs Losses		22.60%		17.30%
Fair Value Inputs Projected Collateral Recoveries		11.30%		15.50%
Fair Value Inputs Projected Collateral Scheduled Amortization		50.10%		51.50%
Income Approach Valuation Technique [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		21.00%		13.50%
Projected Collateral Prepayments		50.30%		41.10%
Fair Value Inputs Losses		9.80%		12.90%
Fair Value Inputs Projected Collateral Recoveries		4.70%		10.10%
Fair Value Inputs Projected Collateral Scheduled Amortization		35.20%		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		$ 18,309,000		$ 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		8.30%		19.20%
Fair Value Inputs Losses		0.90%		0.70%
Fair Value Inputs Projected Collateral Recoveries		4.60%		1.50%
Fair Value Inputs Projected Collateral Scheduled Amortization		65.00%		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		36.40%		25.00%
Fair Value Inputs Losses		4.60%		2.30%
Fair Value Inputs Projected Collateral Recoveries		30.90%		14.30%
Fair Value Inputs Projected Collateral Scheduled Amortization		94.40%		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		21.90%		22.10%
Fair Value Inputs Losses		2.80%		1.60%
Fair Value Inputs Projected Collateral Recoveries		13.60%		8.40%
Fair Value Inputs Projected Collateral Scheduled Amortization		83.60%		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		$ 1,693,000		$ 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		17.80%		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		82.20%		82.00%
LIBOR OAS		12.20%	[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		74.50%		70.40%
Fair Value Inputs Projected Collateral Scheduled Amortization		25.50%		29.60%
Total Outstanding Collateral		100.00%		100.00%
LIBOR OAS		6.92%	[1]	6.22%	[2]
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 10,276,000		$ 13,920,000
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		16.90%		15.00%
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		16.90%		20.00%
Income Approach Valuation Technique [Member] | Corporate debt and warrants [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		16.90%		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		$ 119,099,000		$ 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		7.90%		9.00%
Projected Collateral Prepayments		0.00%		0.00%
Fair Value Inputs Losses		0.90%		1.00%
Fair Value Inputs Projected Collateral Scheduled Amortization		0.00%		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		24.90%		15.00%
Projected Collateral Prepayments		42.70%		40.90%
Fair Value Inputs Losses		97.10%		33.80%
Fair Value Inputs Projected Collateral Scheduled Amortization		85.40%		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		10.60%		10.40%
Projected Collateral Prepayments		34.60%		30.90%
Fair Value Inputs Losses		8.50%		7.30%
Fair Value Inputs Projected Collateral Scheduled Amortization		56.90%		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		$ 33,383,000		$ 43,847,000
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		8.00%		9.80%
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		17.20%		17.60%
Income Approach Valuation Technique [Member] | Performing Commercial Mortgage Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		11.20%		11.90%
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 40,576,000		$ 13,848,000
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		4.80%		5.50%
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		14.90%		8.00%
Income Approach Valuation Technique [Member] | Performing Residential Mortgage Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Yield		6.70%		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		$ 5,358,000		$ 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		7.00%		5.70%
Months to Resolution		6 months		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		9.00%		7.90%
Months to Resolution		38 months 3 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		8.30%		7.30%
Months to Resolution		20 months 6 days		20 months 18 days
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		$ 25,311,000		$ 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		5 months 27 days		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		19.80%		19.40%
Months to Resolution		125 months 18 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		14.70%		13.70%
Months to Resolution		27 months 3 days		9 months 10 days
Credit Default Swaps On Asset Backed Securities [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value		$ 5,595,000		$ 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		20.30%		26.60%
Fair Value Inputs Losses		14.90%		15.00%
Fair Value Inputs Projected Collateral Recoveries		5.10%		6.80%
Fair Value Inputs Projected Collateral Scheduled Amortization		39.30%		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		29.70%		44.10%
Fair Value Inputs Losses		29.20%		33.70%
Fair Value Inputs Projected Collateral Recoveries		12.80%		16.90%
Fair Value Inputs Projected Collateral Scheduled Amortization		50.00%		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		24.50%		32.60%
Fair Value Inputs Losses		22.90%		26.50%
Fair Value Inputs Projected Collateral Recoveries		7.90%		12.00%
Fair Value Inputs Projected Collateral Scheduled Amortization		44.70%		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]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		$ (1,027,000)		$ (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		50.70	[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		100.25	[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		87.07	[3]	56.38	[4]
Guarantees [Member] | Recent Transactions [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure				$ (828,000)
Guarantees [Member] | Expected cash flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		$ (150,000)
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		$ 3,030,000		$ 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		16.50%		14.00%
Expected Holding Period (Months)		5 months 27 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)		5 months 27 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		16.50%		14.70%
Expected Holding Period (Months)		5 months 27 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				$ 2,738,000
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	[5]			2.7
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	[5]			2.7
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	[5]			2.7
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		$ 15,000,000		$ 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.