Fair Value - Fair Value Measurement (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assumed Gain/(Loss) From Loan Sale	$ (956)
Interest Rate Movement Effect	982
Servicing Rights Value	4,707
Security Price Change	(909)
Total Fair Value Measurement Gain/(Loss)	3,824
Mortgage Banking [Member] \| Level 2 [Member] \| Fair Value, Measurements, Recurring [Member] \| Rate Lock Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	237,989
Assumed Gain/(Loss) From Loan Sale	(602)
Interest Rate Movement Effect	559
Servicing Rights Value	2,417
Total Fair Value Measurement Gain/(Loss), Rate lock commitments	2,374
Mortgage Banking [Member] \| Level 2 [Member] \| Fair Value, Measurements, Recurring [Member] \| Forward Sales Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	424,966
Security Price Change	(909)
Total Fair Value Measurement Gain/(Loss), Forward sales contracts	(909)
Mortgage Banking [Member] \| Level 2 [Member] \| Fair Value, Measurements, Recurring [Member] \| Mortgages Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	203,305
Assumed Gain/(Loss) From Loan Sale	(354)
Interest Rate Movement Effect	423
Servicing Rights Value	2,290
Total Fair Value Measurement Gain/(Loss), Mortgages held for sale	$ 2,359

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The amount of net gains and losses recognized in income during the period on derivative instruments not designated as hedging instruments.

+ References

No definition available.

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- Definition

Fair value measurement assumed gain (loss) from loan sale.

+ References

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- Definition

Fair value measurement changes attributable to servicing rights value changes.

+ References

No definition available.

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- Definition

Interest rate movement effect on fair value measurement.

+ References

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- Definition

Security price change effect on fair value measurement.

+ References

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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