Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FLOWS PROVIDED BY (USED IN) OPERATING ACTIVITIES:
Net loss including non-controlling interest	$ (13,233)	$ (24,861)	$ (18,418)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	1,767	3,350	4,020
Lease termination charges	3,337	0	0
Goodwill impairment charges	5,698	3,388	0
Increase (decrease) in allowance for doubtful accounts	(19)	(57)	47
Loss on disposal of Grid business	0	254	0
Loss on disposal and write-down of fixed assets	81	5,217	30
Increase in accrued investment income	(31)	(32)	(6)
Stock-based compensation	293	1,197	2,538
Adjustment to contingent consideration	(650)	43	0
Change in operating assets and liabilities:
Accounts receivable	(53)	2,536	5,151
Inventories	409	1,757	5,284
Deferred cost of goods sold	277	209	(797)
Other current assets	356	1,007	450
Accounts payable	(1,309)	(81)	(2,925)
Accrued liabilities	(1,097)	(4,034)	2,605
Deferred revenues	(707)	(846)	978
Deferred rent	(45)	(35)	(36)
Net cash used in operating activities	(4,926)	(10,988)	(1,079)
CASH FLOWS PROVIDED BY (USED IN) INVESTING ACTIVITIES:
Purchases of available-for-sale short-term investments	(16,974)	(28,975)	(46,947)
Proceeds from maturities and sales of available‑for‑sale short‑term investments	28,852	48,000	46,946
Change in other long-term assets	(795)	29	(51)
Cash paid for acquisition, net of cash acquired	0	(924)	0
Proceeds from divestiture of Grid business, net of transaction costs	0	2,144	0
Capital expenditures	(306)	(746)	(971)
Net cash (used in) provided by investing activities	10,777	19,528	(1,023)
CASH FLOWS PROVIDED BY (USED IN) FINANCING ACTIVITIES:
Principal payments of lease financing obligations	(11,278)	(2,064)	(2,056)
Proceeds from exercise of stock options	0	17	0
Restricted investments used as collateral for line of credit	0	(6,250)	0
Repurchase of common stock from employees for payment of taxes on vesting of restricted stock units and upon exercise of stock options	(153)	(422)	(453)
Net cash used in financing activities	(11,431)	(8,719)	(2,509)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	(69)	(1,129)	383
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(5,649)	(1,308)	(4,228)
CASH AND CASH EQUIVALENTS:
Beginning of period	13,340	14,648	18,876
End of period	7,691	13,340	14,648
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for interest on lease financing obligations	387	1,003	1,224
Cash paid for income taxes	249	294	459
Fair value of stock issued in connection with acquisition	0	715	0
Non-cash transfer from financing to investing for restricted investments used as collateral for credit cards	0	1,399	0
Non-cash transfer of restricted investments to available-for-sale short-term investments	$ 0	$ 4,851	$ 0