Loans Receivable, Net - Summary of Loans Individually Evaluated for Impairment by Class of Loans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 36,979	$ 39,903
Allowance for Loan Losses Allocated	2,161	3,647
With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	27,482	26,404
Recorded Investment	26,487	24,457
Average Recorded Investment	30,093	27,432
Interest Income Recognized	1,152	1,055
With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	10,492	15,532
Recorded Investment	10,492	15,446
Allowance for Loan Losses Allocated	2,161	3,647
Average Recorded Investment	10,930	11,155
Interest Income Recognized	184	220
Residential Real Estate [Member] \| With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	12,351	19,559
Recorded Investment	11,931	18,130
Average Recorded Investment	16,253	20,697
Interest Income Recognized	662	813
Residential Real Estate [Member] \| With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	948	62
Recorded Investment	948	62
Allowance for Loan Losses Allocated	88	2
Average Recorded Investment	990	36
Interest Income Recognized	59	1
Commercial [Member] \| Commercial Real Estate [Member] \| With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	12,174	2,303
Recorded Investment	12,142	2,292
Average Recorded Investment	11,396	2,704
Interest Income Recognized	384	110
Commercial [Member] \| Commercial Real Estate [Member] \| With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	9,023	15,128
Recorded Investment	9,023	15,042
Allowance for Loan Losses Allocated	1,741	3,389
Average Recorded Investment	9,196	10,683
Interest Income Recognized	77	217
Construction and Land [Member] \| Commercial Real Estate [Member] \| With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	76
Construction and Land [Member] \| Commercial Real Estate [Member] \| With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance		309
Recorded Investment		309
Allowance for Loan Losses Allocated		223
Average Recorded Investment	152	391
Consumer [Member] \| With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,243	3,435
Recorded Investment	1,700	2,928
Average Recorded Investment	1,982	3,425
Interest Income Recognized	96	124
Consumer [Member] \| With an Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	521	33
Recorded Investment	521	33
Allowance for Loan Losses Allocated	332	33
Average Recorded Investment	592	45
Interest Income Recognized	48	2
Commercial and Industrial [Member] \| With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	714	1,107
Recorded Investment	714	1,107
Average Recorded Investment	386	606
Interest Income Recognized	$ 10	$ 8

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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