Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Finite Lived Intangible Assets Amortization Expense [Line Items]
Impairment charges		$ 0
Amortization Expense	$ 330,000		$ 388,000	$ 999,000	$ 1,163,000
Estimated intangible asset amortization expense in 2015	1,300,000			1,300,000
Estimated intangible asset amortization expense in 2016	1,300,000			1,300,000
Estimated intangible asset amortization expense in 2017	1,300,000			1,300,000
Estimated intangible asset amortization expense in 2018	1,300,000			1,300,000
Estimated intangible asset amortization expense in 2019	$ 1,300,000			$ 1,300,000