Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Accounts receivable, less allowance for doubtful accounts of $12,781 in 2019; $8,325 in 2018	$ 12,781	$ 8,325
Common shares, par value (dollars per share)	$ 0	$ 0.00
Common shares, shares authorized (shares)	63,000	63,000
Common shares, shares issued (shares)	33,550	29,430
Preferred shares, par value (dollars per share)	$ 0	$ 0
Preferred shares, shares authorized (shares)	1,000	1,000
Preferred shares, shares issued (shares)	0	0
Treasury shares, at cost (shares)	207	936

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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