Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets
Allowance for doubtful accounts and discounts	$ 1,100	$ 1,350
Stockholders' equity
Preferred stock, no par value
Preferred stock, shares authorized	2,500	2,500
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, no par value
Common stock, shares authorized	40,000	40,000
Common stock, shares issued	17,274	15,604
Common stock, shares outstanding	17,274	15,604