Loans Receivable and Allowance for Loan Losses - Mortgage Loans Receivable Modified in a Troubled Debt Restructuring with Payments Default (Details) - Mortgage Loans $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($) loan	Dec. 31, 2013 USD ($) loan
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	16	9	37
Recorded investment \| $	$ 4,975	$ 3,463	$ 9,521
Residential \| Full documentation interest-only
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	6	1	11
Recorded investment \| $	$ 2,240	$ 621	$ 2,191
Residential \| Full documentation amortizing
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	6	2	4
Recorded investment \| $	$ 1,749	$ 319	$ 1,334
Residential \| Reduced documentation interest-only
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	2	3	17
Recorded investment \| $	$ 380	$ 1,123	$ 4,190
Residential \| Reduced documentation amortizing
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	2	0	3
Recorded investment \| $	$ 606	$ 0	$ 788
Multi-family
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	0	3	2
Recorded investment \| $	$ 0	$ 1,400	$ 1,018

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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