Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net income (loss)	$ (456)	$ (4,253)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	2,763	2,053
Equity in loss of partnerships	112	71
Stock-based compensation	1,019	1,712
Change in fair value of contingent consideration	90	0
Change in allowance for doubtful accounts	(130)	273
Loss on disposal of assets	0	173
Changes in operating assets and liabilities:
Accounts receivable	682	(260)
Inventories	(2,642)	(3,151)
Contract assets	(2,510)	2,126
Other assets	(474)	161
Accounts payable	1,266	(1,366)
Accrued expenses	2,001	1,912
Other liabilities	(385)	(959)
Net cash provided by (used in) operating activities of continuing operations	1,336	(1,508)
Net cash provided by operating activities of discontinued operation	0	3
Net cash provided by (used in) operating activities	1,336	(1,505)
Cash flows from investing activities:
Purchases of property, plant and equipment	(1,300)	(1,952)
Payments for acquisition of a business	0	(7,128)
Payments for acquisition of other assets	0	(141)
Purchase of investment securities	(11,965)	(6,159)
Proceeds from maturities of investment securities	9,885	15,250
Investment in partnerships, payments	(154)
Investment in partnerships, proceeds		391
Net cash (used in) provided by investing activities	(3,534)	261
Cash flows from financing activities:
Payment of financing leases	(18)	(57)
Payments on liabilities for acquisition of intangible assets	(104)	0
Exercise of stock options and employee stock purchase plan shares	250	107
Withholding of common stock upon vesting of restricted stock units	(308)	(246)
Payment of contingent consideration liabilities	(52)	0
Net cash used in financing activities	(232)	(196)
Effect of exchange rate changes on cash	(115)	(37)
Net decrease in cash	(2,545)	(1,477)
Cash, cash equivalents and restricted cash, beginning of period	9,280	9,162
Cash, cash equivalents and restricted cash, end of period	6,735	7,685
Non-cash investing and financing:
Acquisition of property, plant and equipment in accounts payable	318	213
Acquisition of a business through liabilities incurred	0	3,705
Acquisition of a business through issuance of common stock	$ 0	$ 982