Loans Receivable and Allowance for Loan Losses (TDR Mortgage Loans, Subsequent Payment Default) (Details) - Mortgage Loans $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) loan	Mar. 31, 2015 USD ($) loan
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	9	8
Recorded Investment \| $	$ 3,176	$ 4,203
Residential Mortgage Loans \| Full documentation interest-only
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	2	1
Recorded Investment \| $	$ 533	$ 648
Residential Mortgage Loans \| Full documentation amortizing
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	2	2
Recorded Investment \| $	$ 408	$ 854
Residential Mortgage Loans \| Reduced documentation interest-only
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	4	2
Recorded Investment \| $	$ 1,947	$ 1,314
Residential Mortgage Loans \| Reduced documentation amortizing
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	1	0
Recorded Investment \| $	$ 288	$ 0
Multi-Family
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans \| loan	0	3
Recorded Investment \| $	$ 0	$ 1,387

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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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- Definition

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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