Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Valuation methodologies used for assets measured at fair value
Percentage of non performing loans held for sale, multi-family mortgage	72.00%	80.00%
Percentage of non performing loans held for sale, residential mortgage loans	28.00%	20.00%
Real estate owned, net	$ 12,691	$ 19,798
Weighted average
Valuation methodologies used for assets measured at fair value
Assumption to estimate fair value of servicing asset, weighted average discount rate (as a percent)	9.96%	9.97%
Assumption to estimate fair value of servicing asset, weighted average constant prepayment rate (as a percent)	11.07%	10.47%
Assumption to estimate fair value of servicing asset, weighted average life	5 years 9 months 18 days	6 years 1 month 6 days
Residential Mortgage Loans
Valuation methodologies used for assets measured at fair value
Percentage of impaired loans	85.00%	81.00%
Percentage of impaired loans for which fair value adjustment is recognized	86.00%	80.00%
Period after which loans are individually evaluated for impairment	180 days
Period past due when loan servicer performs property inspections	45 days
Multi Family and Commercial Real Estate
Valuation methodologies used for assets measured at fair value
Percentage of impaired loans	13.00%	17.00%
Percentage of impaired loans for which fair value adjustment is recognized	13.00%	19.00%
Home equity lines of credit
Valuation methodologies used for assets measured at fair value
Percentage of impaired loans	2.00%	2.00%
Percentage of impaired loans for which fair value adjustment is recognized	1.00%	1.00%
Period after which loans are individually evaluated for impairment	90 days
Residential Properties
Valuation methodologies used for assets measured at fair value
Real estate owned, net		$ 17,800
Recurring basis \| Residential mortgage-backed securities
Valuation methodologies used for assets measured at fair value
Percentage of debt securities comprising available for sale securities portfolio	81.00%	83.00%
Percentage available for sale residential mortgage backed securities which are GSE securities	99.00%	99.00%
Recurring basis \| Obligations of GSEs
Valuation methodologies used for assets measured at fair value
Percentage of debt securities comprising available for sale securities portfolio	19.00%	17.00%

The past due period of time after which all loans are individually evaluated for impairment.

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Impaired Loans, Percent

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Percentage Of Available For Sale Residential Mortgage Backed Securities which are Government Sponsored Enterprise Securities.

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Percentage of debt securities comprising securities available-for-sale portfolio.

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Percentage of Non-performing Loans Held-for-sale Comprising Multi-family Mortgage Loans

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 28
-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph c
-Subparagraph Schedule III
-Article 5

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122596-111746

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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