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 income (loss)	$ (12,919)	$ 4,142	$ 9,523
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	10,559	10,612	10,457
(Gain) loss on sale or disposal of Property, equipment and leasehold improvements	(100)	(567)	428
Deferred income taxes	(5,374)	(506)	(5,400)
Stock-based compensation	2,006	1,484	1,316
Impairment of assets held for sale	0	0	493
Lease expense	287	0	0
Other	224	503	539
Changes in operating assets and liabilities:
Accounts receivable, net	12,846	(2,770)	(3,776)
Inventories	(2,199)	(2,728)	5,500
Other current assets	(1,049)	466	(1,840)
Accounts payable and other accrued expenses	6,180	858	(1,323)
Deferred revenue	16,725	2,630	1,600
Accrued salaries, wages and payroll taxes	40	(266)	910
Refundable deposits	(218)	(617)	(1,649)
Net cash provided by operating activities	27,008	13,241	16,778
Cash flows from investing activities:
Expenditures for Property, equipment and leasehold improvements	(14,399)	(12,769)	(18,342)
Proceeds from sale of Property, equipment and leasehold improvements	188	23,017	95
Restricted cash from sale of Property, equipment and leasehold improvements	0	515	0
Business combinations and asset acquisitions	(274)	(37,887)	0
Equity method investment	0	0	(2,101)
Net cash used in investing activities	(14,485)	(27,124)	(20,348)
Cash flows from financing activities:
Proceeds from issuance of long-term debt	5,192	0	0
Principal payments on debt and capital lease obligations	(1,238)	(724)	(709)
Net borrowings (repayments) under revolving line of credit	(17,112)	14,893	4,224
Proceeds from issuances of common stock	248	427	219
Tax payments related to performance shares issued	(344)	(92)	(27)
Net cash provided by (used in) financing activities	(13,254)	14,504	3,707
Increase (decrease) in Cash, cash equivalents and restricted cash	(731)	621	137
Cash, cash equivalents and restricted cash:
Beginning of period	1,200	579	442
End of period	469	1,200	579
Supplemental disclosure of cash flow information:
Cash paid for interest	1,879	576	716
Cash paid for income taxes, net	(1,560)	1,078	1,158
Cash paid for amounts included in measurement of lease liabilities	3,010	0	0
Supplemental disclosure of non-cash information:
Right-of-use assets obtained in exchange for operating lease obligations	24,918	0	0
Right-of-use assets obtained in exchange for finance lease obligations	2,538	0	0
Purchases of Property, equipment and leasehold improvements with capital leases	0	0	521
Purchases of Property, equipment and leasehold improvements included in Accounts payable at end of period	$ 1,593	$ 3,061	$ 519