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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Sep. 30, 2014	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Mar. 31, 2014
Schedule Of Income Tax [Line Items]
Valuation allowance resulting in income tax benefit	$ 3,519,000			$ 3,519,000		$ 5,618,000	$ 13,725,000
Net deferred tax assets	10,079,000			10,079,000		9,490,000
Unrecognized stock-based compensation	92,214,000			92,214,000		101,108,000
NOLs deemed worthless				3,487,000
Deferred tax asset related to NOLs	0			0
Income tax expense/(benefit)	16,766,000		$ 9,531,000	25,724,000	$ (4,194,000)
Gross deferred tax asset	589,000		$ 4,238,000	589,000	4,238,000
Credit to additional paid-in capital for the amount of NOLs from stock-based compensation				25,807,000	$ 5,293,000
State income taxes	156,000			$ 506,000
Income tax rate		38.00%		38.38%
Foreign Subsidiaries [Member]
Schedule Of Income Tax [Line Items]
Deferred tax asset offset by a valuation allowance	$ 1,423,000			$ 1,423,000		$ 816,000
Previously Reported [Member]
Schedule Of Income Tax [Line Items]
Income tax rate		45.00%