Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 1,900,000	$ (20,100,000)	$ (21,300,000)	$ (25,200,000)
Effective income tax rate, continuing operations (as a percent)	(5.70%)	63.40%	14.20%	31.90%
Expected effective tax rate	35.00%	35.00%	35.00%	35.00%
Valuation allowance on deferred tax assets	$ 58,700,000		$ 58,700,000		$ 7,100,000
Valuation allowance on deferred tax assets included in other comprehensive income	$ 8,100,000		$ 8,100,000		$ 0