Loan Sales And Mortgage Servicing Rights - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Loan Sales And Mortgage Servicing Rights [Line Items]
Gain on sale of securitization loans	$ 7,812	$ 2,935
Freddie Mac
Loan Sales And Mortgage Servicing Rights [Line Items]
Payments related to closing of swap position	2,400
Increased pricing on the loan sale	2,200
FFB
Loan Sales And Mortgage Servicing Rights [Line Items]
Sale of multifamily loans through securitization	41,000
Gain on sale of securitization loans	600
Fair value of beneficial interest		900
Mortgage servicing rights	2,200	200
Loans serviced for others	412,200
Servicing fees earned on loans	300	0
FFB \| Freddie Mac
Loan Sales And Mortgage Servicing Rights [Line Items]
Sale of multifamily loans through securitization	265,000	102,000
Gain on sale of securitization loans	$ 7,200	$ 2,700

Fair value of beneficial interest.

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Increased pricing on the loan sale related to swap agreement.

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Loan sales and mortgage servicing rights.

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- Definition

Mortgage servicing rights created from sale of loans.

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Mortgage servicing rights created from sale of loans serviced for others.

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- Definition

Payments related to closing of swap position including fees.

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All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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- Definition

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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The cash inflow from the securitization of loans held for investment. Securitization is the structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities.

+ References

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-SubTopic 10
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