Income tax reconciliation reserves for uncertain tax positions.

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- Definition

Percentage 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

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- Definition

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

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-Glossary Income Tax Expense (or Benefit)

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- Definition

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.

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- Definition

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 nondeductible meals and entertainment expense.

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Income Taxes - Provision for Income Taxes Attributable to Income from Continuing Operations (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 statutory rate (35%)									$ 17,699	$ 14,684	$ 13,355
State taxes (net of federal benefit)									3,361	2,020	970
Business meals and entertainment - non-deductible									667	624	674
Reserves for uncertain tax positions									(1,724)	(531)	(432)
Other, net									151	(220)	(203)
Total income tax expense from continuing operations	$ (2,137)us-gaap_IncomeTaxExpenseBenefit	$ 4,353us-gaap_IncomeTaxExpenseBenefit	$ 4,824us-gaap_IncomeTaxExpenseBenefit	$ 13,114us-gaap_IncomeTaxExpenseBenefit	$ (2,698)us-gaap_IncomeTaxExpenseBenefit	$ 2,707us-gaap_IncomeTaxExpenseBenefit	$ 4,260us-gaap_IncomeTaxExpenseBenefit	$ 12,308us-gaap_IncomeTaxExpenseBenefit	$ 20,154us-gaap_IncomeTaxExpenseBenefit	$ 16,577us-gaap_IncomeTaxExpenseBenefit	$ 14,364us-gaap_IncomeTaxExpenseBenefit
Effective income tax rate									39.90%	39.50%	37.60%