Fair Value Measurements (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Valuation methodologies used for assets measured at fair value
Impaired loans comprising residential mortgage loans (as a percent)	73.00%	81.00%
Impaired loans comprising multi-family and commercial real estate loans (as a percent)	25.00%	19.00%
Percentage of Impaired Loans Comprising Home Equity Lines of Credit	2.00%
Impaired loans for which fair value adjustment is recognized comprising residential mortgage loans (as a percent)	69.00%	83.00%
Impaired loans for which fair value adjustment is recognized comprising multi-family and commercial real estate loans (as a percent)	30.00%	17.00%
Impaired loans for which fair value adjustment is recognized comprising home equity loans (as a percent)	1.00%
Period after which loans are individually evaluated for impairment	180 days
Real estate owned, net	35,723	42,636
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)	9.48%	9.45%
Assumption to estimate fair value of servicing asset, weighted average constant prepayment rate (as a percent)	12.35%	10.52%
Assumption to estimate fair value of servicing asset, weighted average life	5 years 8 months 12 days	6 years 3 months 18 days
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
Real estate owned, net	33,700

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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- Definition

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

+ References

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- Definition

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

+ References

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Represents the percentage of impaired loans comprising residential mortgage loans.

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- Definition

Percentage of Impaired Loans for Which Fair Value Adjustment is Recognized Comprising Home Equity Loans

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- Definition

Represents the percentage of impaired loans for which fair value adjustment is recognized, comprising multi-family and commercial real estate loans.

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No definition available.

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- Definition

Represents the percentage of impaired loans for which fair value adjustment is recognized, comprising residential mortgage loans.

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- Definition

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 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

Reference 3: 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.

+ 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 (d)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

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- Definition

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

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- Definition

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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