Net Deferred Tax Asset (Liability) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Net operating loss and capital loss carryforward - 382 limited	$ 68,210	$ 74,220
Net operating loss carryforward - not 382 limited	40,925	34,774
State net operating loss carryforward, net	3,114
Capital loss carryforward - not 382 limited	35,982	23,106
Company basis difference	17,978	25,176
Reserves and accruals	2,045	291
Equity-based compensation expense	8,926	5,369
AMT and other credits	81
Other, net	1,174us-gaap_DeferredTaxAssetsOther	1,302us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	178,435us-gaap_DeferredTaxAssetsGross	164,238us-gaap_DeferredTaxAssetsGross
Valuation allowance	(151,389)	(150,408)
Deferred tax asset	27,046us-gaap_DeferredTaxAssetsNet	13,830us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Intangible assets	24,132	(13,830)
Total deferred tax liabilities	24,132us-gaap_DeferredIncomeTaxLiabilities	(13,830)us-gaap_DeferredIncomeTaxLiabilities
Total net deferred tax assets	$ 2,914us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred tax assets alternative minimum tax and other credits.

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Deferred tax assets capital net operating and capital loss carry forwards.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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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 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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