Fair Value Measurements - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-performing loans held-for-sale comprising multi-family mortgage loans (as a percent)	80.00%
Non-performing loans held-for-sale comprising residential mortgage loans (as a percent)	20.00%
Number of non-performing loans held-for-sale \| loan		1
Impaired loans comprising residential mortgage loans (as a percent)	81.00%	73.00%
Impaired loans comprising multi-family and commercial real estate loans (as a percent)	17.00%	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)	80.00%	69.00%
Impaired loans for which fair value adjustment is recognized comprising multi-family and commercial real estate loans (as a percent)	19.00%	30.00%
Impaired loans for which fair value adjustment is recognized comprising home equity loans (as a percent)	1.00%	1.00%
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)	10.47%	12.35%
Assumption to estimate fair value of servicing asset, weighted average life	6 years 1 month 2 days	5 years 8 months 16 days
Real estate owned, net	$ 19,798	$ 35,723
Residential
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
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	$ 17,800	$ 33,700
Total residential mortgage-backed securities \| Recurring basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of debt securities comprising available-for-sale portfolio	83.00%	75.00%
Available-for-sale residential mortgage-backed securities portfolio which are GSE securities (as a percent)	99.00%	98.00%
Obligations of GSEs \| Recurring basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of debt securities comprising available-for-sale portfolio	17.00%	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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- Definition

Number of Non-performing Loans, Held-for-sale

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- Definition

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

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- Definition

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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- 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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Represents the percentage of impaired loans for which fair value adjustment is recognized, 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

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

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Percentage of Non-performing Loans Held-for-sale Comprising Residential Mortgage Loans

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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.

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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 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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- Definition

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=56950315&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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