Consolidated Statements of Operations and Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Revenue	$ 233,624	$ 245,555
Cost of services	79,983	90,747
Gross profit	153,641	154,808
Operating expenses:
Sales and marketing	70,091	76,343
General and administrative	52,416	47,680
Total operating expenses	122,507	124,023
Operating income	31,134	30,785
Other income (expense):
Interest expense	(13,359)	(16,488)
Other components of net periodic pension cost	(1,581)	(121)
Other expense	(2,373)	(366)
Income before income tax expense	13,821	13,810
Income tax expense	(5,397)	(4,496)
Net income	8,424	9,314
Other comprehensive income (loss):
Foreign currency translation adjustment, net of tax	(265)	(2,188)
Comprehensive income	$ 8,159	$ 7,126
Net income per common share:
Basic (in dollars per share)	$ 0.24	$ 0.27
Diluted (in dollars per share)	$ 0.22	$ 0.25
Weighted-average shares used in computing basic and diluted net income per common share:
Basic (in shares)	35,186,121	34,606,864
Diluted (in shares)	37,985,785	36,981,652