Stockholders' Equity (Details Textual) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Class of Stock [Line Items]
Amortization of Intangible Assets	$ 1,000	$ 900	$ 1,600	$ 1,800
Unrecognized compensation costs related to restricted stock awards	10,100		$ 10,100
Period of stock option compensation cost recognition			3 years 2 months 5 days
Restricted Stock [Member]
Class of Stock [Line Items]
Compensation cost	$ 1,700	$ 981	$ 3,000	$ 1,600
Shares of restricted stock granted (in shares)	46		174
Grants in the period, aggregate fair value	$ 1,100		$ 3,500
Employee Stock Option [Member]
Class of Stock [Line Items]
Options, issued in period (in shares)	9		152
Options, issued in period, weighted average exercise price	$ 23.49		$ 18.80
Grants in period, aggregate fair value	$ 100		$ 1,100