Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 7,841	$ 5,140
Intangible assets, accumulated amortization	$ 107,461	$ 93,574
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	30,986,702	30,979,827
Common stock, shares outstanding	26,919,455	26,912,580
Treasury stock, shares	4,067,247	4,067,247
Interest rate swaps, income taxes	$ (60)	$ (142)