Loans Receivable and Allowance for Loan Losses - Schedule of FDIC Loss Sharing Receivable (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Receivables [Abstract]
Beginning balance	$ 2,320us-gaap_FDICIndemnificationAsset	$ 10,046us-gaap_FDICIndemnificationAsset
Increased (decreased) estimated cash flows	671	(1,467)
Other activity, net	134	990
Cash payments to/(from) FDIC	302	(1,297)
Ending balance	3,427us-gaap_FDICIndemnificationAsset	8,272us-gaap_FDICIndemnificationAsset
Provision for loan losses	3,635	2,901
Effect attributable to FDIC loss share arrangements	(671)	1,467
Provision for loan losses	$ 2,964us-gaap_ProvisionForLoanAndLeaseLosses	$ 4,368us-gaap_ProvisionForLoanAndLeaseLosses

Cash received from the FDIC relating to claims under indemnification agreements.

No definition available.

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- Definition

FDIC Indemnification Asset Other Period Increase Decrease

+ References

No definition available.

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- Definition

Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

+ References

No definition available.

+ Details

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- Definition

Change in carrying amount of the indemnification asset relating to loss sharing agreements with the Federal Deposit Insurance Corporation (FDIC). The change includes for example, but is not limited to, acquisitions, additional estimated losses, disposals, cash payments, accretion of discount and write-offs, net of recoveries.

+ References

No definition available.

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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Period Type:	duration

- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

+ Details

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