Income tax reconciliation increase in cash value of bank owned life insurance.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Section 50

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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Income Taxes - Schedule of Reconciliation of Differences in Company's Income Tax Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Tax at federal income tax rate									$ 19,672	$ 10,256	$ 7,602
Change resulting from:
Tax-exempt interest									(1,647)	(841)	(675)
Increase in cash value of bank owned life insurance									(568)	(446)	(34)
Other									25	316	392
Provision for income taxes	$ 4,167us-gaap_IncomeTaxExpenseBenefit	$ 5,122us-gaap_IncomeTaxExpenseBenefit	$ 4,270us-gaap_IncomeTaxExpenseBenefit	$ 3,923us-gaap_IncomeTaxExpenseBenefit	$ 88us-gaap_IncomeTaxExpenseBenefit	$ 3,262us-gaap_IncomeTaxExpenseBenefit	$ 3,329us-gaap_IncomeTaxExpenseBenefit	$ 2,606us-gaap_IncomeTaxExpenseBenefit	$ 17,482us-gaap_IncomeTaxExpenseBenefit	$ 9,285us-gaap_IncomeTaxExpenseBenefit	$ 7,285us-gaap_IncomeTaxExpenseBenefit