Goodwill and Other Intangible Assets Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 129,705		$ 129,705	$ 123,031
Total other intangible assets, net	102,437		102,437	$ 100,935
Amortization expense of intangible assets	3,238	$ 3,029	8,905
Estimated Future Amortization Expense by Fiscal Year [Abstract]
Remainder of 2015	3,200		3,200
2016	12,800		12,800
2017	12,500		12,500
2018	10,500		10,500
2019	8,800		8,800
2020	4,000		4,000
After 2020	$ 1,900		$ 1,900