Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Stock option compensation	$ 5,313	$ 5,232
State credit carry forward	1,725	2,380
Capital loss on sale of Tinet stock	21,531	21,580
Accrued other	3,320	3,075
Total deferred tax assets	31,889	32,267
Deferred tax liabilities:
Depreciation	(7,102)	(3,898)
Prepaids	(1,008)	(732)
Total deferred tax liabilities	(8,110)	(4,630)
Valuation allowance	(22,720)	(23,517)
Net deferred income tax asset	$ 1,059	$ 4,120