CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating Activities:
Net loss	$ (1,220)	$ (12,467)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	479	530
Amortization of premiums and discounts on investments	65	244
Amortization of intangible assets and other	16	801
Stock-based compensation	295	1,776
Changes in assets and liabilities:
Accounts receivable, net	(2,188)	(176)
Prepaid expenses and other current assets	572	122
Other long-term assets	123	(5)
Accounts payable	(292)	350
Accrued compensation	(632)	(363)
Other accrued liabilities	(585)	(1,534)
Other long-term liabilities	(48)	(324)
Deferred revenue	(664)	444
Net cash used in operating activities	(4,079)	(10,602)
Investing Activities:
Purchases of property and equipment	(32)	(481)
Purchases of investments	(14,939)	(22,901)
Maturities of investments	23,273	22,109
Net cash provided by (used in) investing activities	8,302	(1,273)
Financing Activities:
Proceeds from employee stock purchase plan	27	45
Repurchase of common stock	(2)	(72)
Net cash provided by (used in) financing activities	25	(27)
Effect of exchange rate changes on cash and cash equivalents	116	35
Net increase (decrease) in cash and cash equivalents	4,364	(11,867)
Cash and cash equivalents at beginning of period	16,890	27,598
Cash and cash equivalents at end of period	21,254	15,731
Supplemental schedule of cash flow information:
Income taxes paid	$ 85	$ 132