Fair Value Measurements (Narrative) (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)
Valuation methodologies used for assets measured at fair value
Percentage of non performing loans held for sale, multi-family mortgage	80.00%
Percentage of non performing loans held for sale, residential mortgage loans	20.00%
Impaired loans comprising residential mortgage loans (as a percent)	80.00%	73.00%
Impaired loans comprising multi-family and commercial real estate loans (as a percent)	18.00%	25.00%
Impaired Loans comprising home equity lines of credit (as a percent)	2.00%	2.00%
Impaired loans for which fair value adjustment is recognized comprising residential mortgage loans (as a percent)	78.00%	69.00%
Impaired loans for which fair value adjustment is recognized comprising multi-family and commercial real estate loans (as a percent)	21.00%	30.00%
Impaired loans for which fair value adjustment is recognized comprising home equity lines of credit (as a percent)	1.00%	1.00%
Real estate owned, net	$ 19,146	$ 35,723
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)	9.97%	9.48%
Assumption to estimate fair value of servicing asset, weighted average constant prepayment rate (as a percent)	11.62%	12.35%
Assumption to estimate fair value of servicing asset, weighted average life	6 years	5 years 8 months 11 days
Non Performing Multi Family Mortgage Loans
Valuation methodologies used for assets measured at fair value
Non-Performing Number Of Loans		1
Residential Mortgage Loans
Valuation methodologies used for assets measured at fair value
Period after which loans are individually evaluated for impairment	180 days
Period past due when loan servicer performs property inspections	45 days
Home equity lines of credit
Valuation methodologies used for assets measured at fair value
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	$ 17,100	$ 33,700
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	78.00%	75.00%
Percentage available for sale residential mortgage backed securities which are GSE securities	99.00%	98.00%
Recurring basis \| Obligations of GSEs
Valuation methodologies used for assets measured at fair value
Percentage of debt securities comprising available for sale securities portfolio	22.00%	25.00%

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

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Represents the period of time past due when loan servicer performs property inspections to monitor and manage collateral.

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Non-Performing Number Of Loans

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

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Represents the percentage of impaired loans comprising home equity lines of credit.

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Represents the percentage of impaired loans comprising multi-family and commercial real estate loans.

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Represents the percentage of impaired loans comprising residential mortgage loans.

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Represents the percentage of impaired loans for which fair value adjustment is recognized, comprising home equity lines of credit.

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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

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-Number 210

-Section 28

-Article 12

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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

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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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