Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Allowance for credit losses	$ 1,665	$ 3,469
Shareholders' equity:
Common stock, par value (USD per share)	$ 0	$ 0
Common stock, shares authorized	240,000	240,000
Common stock, shares issued	150,715	150,341

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

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Face amount or stated value per share of common stock.

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