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Fair Value Measurement - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 05, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Redeemable Convertible preferred stock, shares issued		600,000		600,000		600,000
Expected volatility rate				40.00%		40.00%
Risk free interest rate				0.40%		0.60%
Expected probability of occurrence				90.00%		90.00%
Mandatory conversion, expected term				9 months		12 months
Net income		$ 22,409	$ (73,483)	$ 77,959	$ (67,982)	$ (61,833)
Maximum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Percentage of closing stock price				10.00%
Estimated net income				$ 40,500
Maximum [Member] \| Volatility Assumption [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Percentage of closing stock price				10.00%
Estimated net income				$ 5,600
Maximum [Member] \| Transaction Occurring Assumption [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Percentage of closing stock price				10.00%
Estimated net income				$ 4,700
Minimum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Preferred stock liquidation preference per share		$ 10.00		$ 10.00
Percentage of closing stock price				10.00%
Estimated net income				$ 43,500
Minimum [Member] \| Volatility Assumption [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Percentage of closing stock price				10.00%
Estimated net income				$ 4,300
Minimum [Member] \| Transaction Occurring Assumption [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Percentage of closing stock price				10.00%
Estimated net income				$ 4,700
Redeemable Convertible Series B Preferred Stock [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Capital	$ 600,000
Redeemable Convertible preferred stock, shares issued	600,000	600,000		600,000		600,000
Preferred stock liquidation preference per share	$ 1,000
Preferred stock dividend rate calculated on interest rate	3.00%
Conversion floor price of common stock		$ 1.75		$ 1.75
Redeemable Convertible Series B Preferred Stock [Member] \| Maximum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Common stock value per share		$ 2.25		$ 2.25