Loans Receivable and Allowance for Loan Losses - Mortgage Loans Receivable by Segment and Class, Subsequent Payment Default (Details) - Mortgage Loans $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) loan	Mar. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	9	9
Recorded Investment \| $	$ 3,707	$ 3,176
Residential \| Full documentation interest-only
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	3	2
Recorded Investment \| $	$ 1,078	$ 533
Residential \| Full documentation amortizing
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	4	2
Recorded Investment \| $	$ 1,566	$ 408
Residential \| Reduced documentation interest-only
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	2	4
Recorded Investment \| $	$ 1,063	$ 1,947
Residential \| Reduced documentation amortizing
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1
Recorded Investment \| $	$ 0	$ 288

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.

No definition available.

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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=66008989&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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