Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Assets Sold Under Agreements To Repurchase [Line Items]
Long-term debt, fair value	$ 522,000,000		$ 513,500,000
Long-term debt, carrying value	$ 507,000,000		$ 500,000,000
Interest percentage	6.00%
Debt maturity period	2022
Gain/Loss on remeasurement of contingent consideration	$ (1,000,000)	$ 0
Accretion expenses for acquisition-related contingent consideration	$ 200,000	$ 200,000
6.0% Senior Notes Due 2022
Assets Sold Under Agreements To Repurchase [Line Items]
Interest percentage	6.00%
Debt maturity period	2022		2022