Deferred Income Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2012
Deferred tax assets:
Loss and credit carryforwards	$ 7,212	$ 16,606
Accrued expenses	2,221	620
Stock-based compensation	7,752	5,200
Total deferred tax assets	17,185us-gaap_DeferredTaxAssetsGross	22,426us-gaap_DeferredTaxAssetsGross
Valuation allowance	(910)	(902)
Net deferred tax assets	16,275us-gaap_DeferredTaxAssetsNet	21,524us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Fixed assets	(2,721)	(1,145)
Intangible assets	(104,973)	(105,435)
Investment in partnership		(1,751)
Total deferred tax liabilities	(107,694)us-gaap_DeferredTaxLiabilities	(108,331)us-gaap_DeferredTaxLiabilities	(8,200)us-gaap_DeferredTaxLiabilities
Net deferred tax liability	$ (91,419)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (86,807)us-gaap_DeferredTaxAssetsLiabilitiesNet

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs.

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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 intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from investments in unconsolidated subsidiaries and investments in other affiliates which are not controlled nor consolidated.

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