Combination of subsidiaries tax years.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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-Publisher FASB

-Name Accounting Standards Codification

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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-Topic 740

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

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Amount of interest expense for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Operating Loss Carryforwards, Valuation Allowance	$ 69,900,000
Statutory U.S. federal rate	35.00%	35.00%	35.00%
Unrecognized tax benefits	59,404,900us-gaap_UnrecognizedTaxBenefits	7,343,500us-gaap_UnrecognizedTaxBenefits	3,951,100us-gaap_UnrecognizedTaxBenefits	2,467,300us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits recognition impact on effective tax rate	33,100,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	5,900,000	400,000
Unrecognized Tax Benefits, Interest on Income Taxes Expense	2,300,000	100,000	0
State and Local Jurisdiction
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Operating loss carryforwards	22,000,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ 4,500,000
Minimum
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Combination of subsidiaries, tax years	3 years
Maximum
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Combination of subsidiaries, tax years	4 years