Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities
Net loss	$ (31,491,000)	$ (16,480,000)	$ (33,349,000)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities
Impairment of goodwill	2,797,000	0	0
Depreciation	4,758,000	6,035,000	6,993,000
Amortization of internally developed software	3,669,000	2,988,000	2,550,000
Amortization of intangible assets	2,850,000	3,080,000	3,134,000
(Gain) loss on disposal of property and equipment	(11,000)	(3,000)	19,000
Unrealized foreign currency losses (gains)	986,000	(419,000)	(216,000)
Non-cash interest expense related to debt agreements	15,000	27,000	42,000
Stock-based compensation related to equity awards and restricted stock	4,704,000	10,295,000	15,619,000
Provision for bad debts	1,507,000	2,328,000	1,210,000
Deferred income tax benefits	(358,000)	(305,000)	(177,000)
Excess tax benefits from stock-based award activities	0	0	(3,000)
Payment of contingent consideration for prior acquisition	0	(93,000)	0
Changes in operating assets and liabilities, net of effect of acquisition
Accounts receivable	4,754,000	795,000	(2,986,000)
Prepaid expenses and other current assets	(268,000)	546,000	575,000
Other assets	(42,000)	(346,000)	348,000
Accounts payable	306,000	741,000	(1,597,000)
Deferred revenues	(346,000)	(628,000)	(625,000)
Accrued expenses and other liabilities	1,300,000	(2,480,000)	1,953,000
Net cash (used in) provided by operating activities	(4,870,000)	6,081,000	(6,510,000)
Investing activities
Purchases of property and equipment	(461,000)	(1,207,000)	(8,584,000)
Proceeds from disposal of property and equipment	11,000	5,000	0
Capitalization of internally developed software	(2,068,000)	(4,712,000)	(5,568,000)
Acquisition of business, net of cash acquired	0	0	(7,738,000)
Net cash used in investing activities	(2,518,000)	(5,914,000)	(21,890,000)
Financing activities
Repayments of capital lease obligations and other debt agreements	(1,160,000)	(1,436,000)	(3,649,000)
Debt issuance costs	0	0	(53,000)
Repurchases of unvested shares	0	0	(2,000)
Employee taxes paid for withheld shares upon equity award settlement	(604,000)	(362,000)	(571,000)
Proceeds from exercises of common stock options	0	390,000	1,439,000
Proceeds from employee stock purchase plan, net	312,000	663,000	968,000
Excess tax benefits from stock-based award activities	0	0	3,000
Net cash used in financing activities	(1,452,000)	(745,000)	(1,865,000)
Effect of foreign exchange rate changes on cash and cash equivalents and restricted cash	1,964,000	(1,035,000)	(662,000)
Net decrease in cash and cash equivalents and restricted cash	(6,876,000)	(1,613,000)	(30,927,000)
Beginning of year	35,713,000	37,326,000	68,253,000
End of year	28,837,000	35,713,000	37,326,000
Supplemental disclosures of other cash flow information
Cash paid for interest	210,000	189,000	106,000
Cash paid for income taxes	1,491,000	728,000	404,000
Supplemental disclosure of non-cash investing and financing activities
Acquisition of equipment through capital leases	852,000	1,864,000	2,350,000
Purchases of property and equipment recorded in accounts payable and accrued expenses	30,000	5,000	0
Issuance of common stock under employee stock purchase plan	362,000	548,000	1,035,000
Issuance of common stock in connection with acquisition of business	$ 0	$ 0	$ 4,338,000