Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounts receivable, allowances for doubtful accounts	$ 1,210	$ 4,466
Common stock, par value (in dollars per share)	$ 0.25
Common stock, shares authorized	360,000,000
Common stock, shares issued	110,834,088
Treasury stock, shares	11,033,098	11,525,725