Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation Allowance [Line Items]
Statutory federal income tax rate	35.00%	35.00%	35.00%
Deferred tax assets, valuation allowance, increase	$ 22,100,000	$ 300,000
Deferred tax assets, valuation allowance, decrease	(16,700,000)	(24,100,000)
Federal net operating loss carryforwards for income tax purposes	521,100,000
State net operating loss carryforwards for income tax purposes	32,000,000
Unrecognized tax benefits impacting effective tax rate	3,400,000	500,000
Deferred tax asset subject to valuation allowance	18,400,000	17,900,000
Significant adjustments	0
Reversal of uncertain tax position (less than)	100,000	100,000	$ 100,000
Interest and penalties accrued	800,000	$ 300,000
Equity-based deferred tax assets [Member]
Valuation Allowance [Line Items]
Deferred tax assets, valuation allowance	$ 192,300,000
Minimum [Member]
Valuation Allowance [Line Items]
Federal net operating loss carryforward expiration period	2020
Maximum [Member]
Valuation Allowance [Line Items]
Federal net operating loss carryforward expiration period	2031