Fair Value (Details) - Unobservable Inputs Used In The Valuation of CDOs - CDOs	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Minimum
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Probability of prepayment	0.00%	0.00%
Probability of default	16.60%	16.70%
Loss given default	93.30%	93.30%
Probability of deferral cure	0.00%	7.60%
Maximum
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Probability of prepayment	10.90%	10.90%
Probability of default	44.10%	46.80%
Loss given default	99.10%	98.90%
Probability of deferral cure	100.00%	100.00%

Represents the probability of deferral cure for each CDO.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Loss, including interest and principal, incurred on a defaulted security, expressed as a percentage of the original principal balance, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

+ Details

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- Definition

Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

+ References

+ Details

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