Loans Receivable and Allowance for Loan Losses - Mortgage Loans Receivable by Segment and Class, Modified in a Troubled Debt Restructuring (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	10	12
Pre- Modification Recorded Investment	$ 2,597	$ 4,165
Recorded Investment	$ 2,558	$ 4,149
Residential \| Full documentation interest-only
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	4
Pre- Modification Recorded Investment	$ 196	$ 888
Recorded Investment	$ 189	$ 889
Residential \| Full documentation amortizing
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	2	2
Pre- Modification Recorded Investment	$ 485	$ 591
Recorded Investment	$ 482	$ 589
Residential \| Reduced documentation interest-only
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	3	3
Pre- Modification Recorded Investment	$ 1,121	$ 1,691
Recorded Investment	$ 1,099	$ 1,686
Residential \| Reduced documentation amortizing
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	4	3
Pre- Modification Recorded Investment	$ 795	$ 995
Recorded Investment	$ 788	$ 985

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No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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