Loans Receivable, Net - Recorded Investment in Residential and Consumer Loans Based on Payment Activity (Detail) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Non-performing	$ 20,905,000	$ 18,307,000
Total loans	1,802,256,000	1,718,687,000
Residential Real Estate [Member] \| Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	796,102,000	782,326,000
Non-performing	4,288,000	3,115,000
Total loans	800,390,000	785,441,000
Residential Real Estate [Member] \| Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	190,450,000	197,472,000
Non-performing	1,901,000	1,877,000
Total loans	$ 192,351,000	$ 199,349,000

Credit quality of loan receivables performing.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

+ Details

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

+ Details

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- Details

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