Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment	$ 30,293	$ 31,253
Less accumulated depreciation	(26,861)	(28,746)
Property and equipment, net	3,432	2,507
Tenant improvements
Property, Plant and Equipment [Line Items]
Property and equipment	1,335	1,226
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	837	819
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment	$ 28,121	$ 29,208