Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net loss from continuing operations, net of income taxes	$ (9,007)	$ (9,230)	$ (19,700)
Net income (loss) from discontinued operations, net of income taxes	0	(136)	21,927
Adjustments required to reconcile net (loss) income to net cash provided by (used in) operating activities:
Depreciation and amortization expense	1,486	3,705	7,760
Gain on sale of discontinued operations, before income taxes	0	0	(14,958)
Amortization of acquired technology	190	0	0
Bad debt expense	27	190	356
Amortization of operating lease right-of-use-asset	4,035	0	0
Mark-to-market expense	0	0	148
Compensation expense related to the acquisition-contingent consideration	0	0	1,810
Deferred tax expense (benefit)	6	(4)	(442)
Loss on disposal of property and equipment	53	21	392
Stock based compensation expense	5,759	3,820	5,394
Net change in operating assets and liabilities:
Increase in accounts receivable	(53,616)	(43,283)	(19,891)
Decrease in contingent consideration on acquisition	0	0	(4,753)
Increase in prepaid expenses, other current assets and other long-term assets	(2,087)	(1,781)	(3,157)
Increase in accounts payable and accrued expenses	59,407	48,779	13,831
Increase (decrease) in other current liabilities	710	322	(126)
Decrease in operating lease liability	(4,788)	0	0
Increase (decrease) in deferred rent and security deposits payable	7	488	(629)
(Decrease) increase in deferred income	0	(619)	1,407
Increase (decrease) in other liabilities	100	(512)	0
Net cash provided by (used in) in operating activities	2,282	1,760	(10,631)
Cash flows from investing activities:
Purchase of property and equipment	(161)	(2,740)	(1,113)
Purchase of patents not subject to amortization	(41)	0	0
Acquisition, net of cash acquired	0	(4,771)	0
Cash received from sale of discontinued operations	0	0	49,000
Expenses paid with respect to sale of discontinued operations	0	0	(1,954)
Net cash (used in) provided by investing activities	(202)	(7,511)	45,933
Cash flows from financing activities:
Proceeds from issuance of common stock under employee stock purchase plan	511	523	446
Payment of contingent consideration on acquisition	(1,500)	0	0
Proceeds from the exercise of stock option awards	6,749	1,845	699
Principal portion of capital lease payments	0	0	(214)
Treasury stock — repurchase of stock	0	(23,537)	(2,406)
Tax withholdings related to net share settlements of restricted stock units	(1,391)	(1,312)	(1,842)
Net cash provided by (used in) financing activities	4,369	(22,481)	(3,317)
Net increase (decrease) in cash and cash equivalents	6,449	(28,232)	31,985
Effect of exchange rate changes in cash and cash equivalents	56	(429)	405
Cash, cash equivalents at beginning of year	47,659	76,320	43,930
Cash, cash equivalents at end of year	$ 54,164	$ 47,659	$ 76,320