Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Accruals and reserves	$ 36,633	$ 38,931
State net operating loss carryforwards	10,307	10,194
Fair value of interest rate swaps	4,203	6,185
Interest and state taxes associated with the liability for uncertain income tax positions	1,842	1,910
Other	792us-gaap_DeferredTaxAssetsOther	701us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	53,777us-gaap_DeferredTaxAssetsNet	57,921us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Basis difference in inventory	(1,597)	(1,636)
Basis difference in property and equipment	(9,655)	(1,978)
Basis difference in goodwill	(72,696)	(57,028)
Other	(3,861)us-gaap_DeferredTaxLiabilitiesOther	(2,328)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liability	(87,809)us-gaap_DeferredTaxLiabilities	(62,970)us-gaap_DeferredTaxLiabilities
Valuation allowance	(6,534)	(6,758)
Net deferred tax asset (liability)	$ (40,566)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (11,807)us-gaap_DeferredTaxAssetsLiabilitiesNet

Interest and state taxes associated with the entity's liability for uncertain income tax positions.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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