Intangible and Other Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense for intangible assets	$ 915	$ 1,235	$ 1,313
Estimated amortization expense for intangible assets for year one	638
Estimated amortization expense for intangible assets for year two	565
Estimated amortization expense for intangible assets for year three	279
Estimated amortization expense for intangible assets for year four	17
Estimated amortization expense for intangible assets for year five	$ 0