Loans Receivable and Related Allowance for Loan Losses - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan_pool loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchase of residential mortgage loans	$ 6,900	$ 19,200
Number of loan pools purchased \| loan_pool		2
Deferred costs	1,300	$ 835
Loans classified as TDRs	239	835
Allowance loan losses allocated to TDRs	19	$ 63
Number of loan modified \| loan		0
Home equity loans and lines of credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans classified as TDRs	$ 10
Number of loan modified \| loan	1
Residential first mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modified \| loan	1	1
Loans receivable in payment default	$ 10	$ 91

Allowance for losses allocated to loans classified as TDRs as at the reporting date

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- Definition

Loans and Leases, Number of Loan Pools Purchased

+ References

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- Definition

Payments to Purchase Mortgage Loans Held-for-sale, Principal Balance

+ References

No definition available.

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- Definition

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+ References

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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- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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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

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 deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65890831&loc=d3e10152-111534

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