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.

Income Taxes (Components of income tax expense (benefit)) (Detail) (USD $)	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
Current income taxes:
Federal									$ 13,671,000us-gaap_CurrentFederalTaxExpenseBenefit	$ 15,391,000us-gaap_CurrentFederalTaxExpenseBenefit	$ 11,199,000us-gaap_CurrentFederalTaxExpenseBenefit
State									3,103,000	3,824,000	2,913,000
Total current									16,774,000us-gaap_CurrentIncomeTaxExpenseBenefit	19,215,000us-gaap_CurrentIncomeTaxExpenseBenefit	14,112,000us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred income taxes:
Federal									554,000	2,743,000	3,116,000
State									254,000	605,000	817,000
Total deferred									808,000us-gaap_DeferredIncomeTaxExpenseBenefit	3,348,000us-gaap_DeferredIncomeTaxExpenseBenefit	3,933,000us-gaap_DeferredIncomeTaxExpenseBenefit
Total income tax expense	$ 4,086,000us-gaap_IncomeTaxExpenseBenefit	$ 5,428,000us-gaap_IncomeTaxExpenseBenefit	$ 2,722,000us-gaap_IncomeTaxExpenseBenefit	$ 5,346,000us-gaap_IncomeTaxExpenseBenefit	$ 4,505,000us-gaap_IncomeTaxExpenseBenefit	$ 6,419,000us-gaap_IncomeTaxExpenseBenefit	$ 6,353,000us-gaap_IncomeTaxExpenseBenefit	$ 5,286,000us-gaap_IncomeTaxExpenseBenefit	$ 17,582,000us-gaap_IncomeTaxExpenseBenefit	$ 22,563,000us-gaap_IncomeTaxExpenseBenefit	$ 18,045,000us-gaap_IncomeTaxExpenseBenefit