CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, reserves (in dollars)	$ 1,603	$ 817
Preferred shares, no par value	$ 0	$ 0
Preferred shares, authorized	5,000,000	5,000,000
Preferred shares, issued	0	0
Common shares, no par value	$ 0	$ 0
Common shares, authorized	60,000,000	60,000,000
Common shares, issued	28,966,000	28,966,000
Common shares, outstanding	27,164,000	27,006,000
Common shares held in treasury, shares	1,802,000	1,960,000

Amount of allowance for credit loss on accounts receivable, classified as current.

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