Income Taxes - Provision for Income Taxes From Continuing Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$ 7,616us-gaap_CurrentFederalTaxExpenseBenefit	$ 5,289us-gaap_CurrentFederalTaxExpenseBenefit	$ 1,213us-gaap_CurrentFederalTaxExpenseBenefit
State	1,369	677	194
Current Income Tax Expense (Benefit), Total	8,985us-gaap_CurrentIncomeTaxExpenseBenefit	5,966us-gaap_CurrentIncomeTaxExpenseBenefit	1,407us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred:
Federal	(676)	(1,554)	(794)
State	298	(196)	(58)
Deferred Income Tax Expense (Benefit), Total	(378)us-gaap_DeferredIncomeTaxExpenseBenefit	(1,750)us-gaap_DeferredIncomeTaxExpenseBenefit	(852)us-gaap_DeferredIncomeTaxExpenseBenefit
Total tax expense	$ 8,607us-gaap_IncomeTaxExpenseBenefit	$ 4,216us-gaap_IncomeTaxExpenseBenefit	$ 555us-gaap_IncomeTaxExpenseBenefit

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations.