Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Statement Of Financial Position [Abstract]
Receivables, allowance for doubtful accounts	$ 1,054	$ 1,240
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	19,191,000	19,184,000
Common stock, shares outstanding	19,191,000	19,184,000