Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended					6 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019		Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ (1,775)	$ (1,738)	$ (875)	[1]	$ 1,520	$ (3,513)	$ 645
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization						509	1,035
Operating lease asset amortization						1,664	1,734
Impairment of long-lived assets	9		0			1,078	0
(Gain) loss on disposal of assets						142	(35)
Stock-based compensation						411	378
Deferred income taxes						(220)	624
Exchange (gain) loss						(3)	134
Changes in operating assets and liabilities:
Accounts receivable-trade						(60)	(45)
Inventory						(6,954)	7,183
Prepaid expenses						(63)	469
Other current assets						(7)	26
Accounts payable-trade						834	(675)
Accrued expenses and other liabilities						(679)	(2,339)
Income taxes, net						(869)	(1,541)
Other assets						(1,664)	(218)
Operating lease liabilities						(1,737)	(1,677)
Total adjustments						(7,618)	5,053
Net cash provided by (used in) operating activities						(11,131)	5,698
Cash flows from investing activities:
Purchase of property and equipment						(285)	(136)
Purchase of short-term investments						(1,697)	(10,679)
Proceeds from sales of assets						1	85
Proceeds from sales of short-term investments						6,310	1,680
Net cash provided by (used in) investing activities						4,329	(9,050)
Cash flows from financing activities:
Proceeds from long-term debt						402	0
Payments on long-term debt						0	(8,968)
Repurchase of treasury stock						0	(724)
Net cash provided by (used in) financing activities						402	(9,692)
Effect of exchange rate changes on cash and cash equivalents						(91)	248
Net decrease in cash and cash equivalents						(6,491)	(12,796)
Cash and cash equivalents, beginning of period		$ 15,905			$ 24,070	15,905	24,070	$ 24,070
Cash and cash equivalents, end of period	$ 9,414		$ 11,274			$ 9,414	$ 11,274	$ 15,905

[1] For the three months ended June 30, 2019, there were 2,290 shares, respectively excluded from the diluted EPS calculation because the impact of their assumed vesting would be anti-dilutive due to a net loss in that period.