CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 12,120	$ 5,464	$ 462
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,372	5,544	6,969
Stock-based compensation expense	8,359	5,992	6,139
Deferred income taxes	1,561	4,145	1,975
Loss on disposal or sale of assets	0	254	1,828
Allowance for doubtful accounts	(136)	1,764	1,422
Excess tax benefits from stock-based awards	(539)	(948)	(1,260)
Asset impairment charges	18	266	836
Impairment of investments	0	4,000	0
Other non-cash (income) charges	328	(555)	279
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable	429	(6,454)	(5,565)
Decrease in inventories	0	386	1,836
Decrease (increase) in other assets	108	(1,502)	3,778
Increase (decrease) in accrued compensation and benefits	128	(212)	2,955
Increase (decrease) in accounts payable and accrued expenses	1,796	613	(2,552)
Increase (decrease) in deferred revenue	(1,888)	1,740	1,547
Decrease in deferred rent	(766)	(681)	(747)
Increase (decrease) in other liabilities, net	(500)	732	113
Net cash provided by operating activities	27,390	20,548	20,015
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisitions, net of cash acquired	(1,359)	(5,647)	(5,725)
Additions to capitalized software	(4,142)	(3,096)	(4,282)
Payment to acquire investments	(295)	(2,500)	(4,000)
Maturity of U.S. Treasury Bills	3,842	2,600	2,599
Purchases of U.S. Treasury Bills	(2,490)	(2,595)	(2,599)
Decrease in cash associated with disposition	0	0	(1,640)
Purchases of property and equipment	(155)	(453)	(786)
Other investing activities, net	(202)	114	(57)
Net cash used in investing activities	(4,801)	(11,577)	(16,490)
CASH FLOWS FROM FINANCING ACTIVITIES
Surrender of restricted common stock for income tax purposes	(2,904)	(3,055)	(4,796)
Repurchase of common stock	(3,961)	(8,807)	(1,628)
Excess tax benefits from stock-based awards	539	948	1,260
Proceeds pursuant to employee stock-based compensation plans	931	497	897
Net cash used in financing activities	(5,395)	(10,417)	(4,267)
Increase (decrease) in cash and cash equivalents	17,194	(1,446)	(742)
Cash and cash equivalents at beginning of year	88,509	89,955	90,697
Cash and cash equivalents at end of year	105,703	88,509	89,955
Supplemental information:
Cash paid for income taxes, net of refunds	$ 3,519	$ 4,305	$ 475