Condensed Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows - operating activities
Net income	$ 24,568,000	$ 42,616,000
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	8,692,000	5,241,000
Deferred income taxes	6,446,000	(246,000)
Stock-based compensation expense	3,772,000	7,482,000
Accretion expense related to earnout payments	642,000	545,000
Gain on marketable securities	(1,694,000)	0
Loss on disposal of property and equipment	131,000	309,000
Impairment charges	7,246,000	0
Changes in assets and liabilities:
Accounts receivable	(59,990,000)	(84,783,000)
Accounts payable	(2,914,000)	(3,944,000)
Accrued expenses	(273,811,000)	(124,281,000)
Deferred revenue	543,000	(1,527,000)
Income taxes recoverable and payable, net	(2,588,000)	(8,114,000)
Retirement and pension plan assets and liabilities	6,403,000	3,297,000
Prepaid expenses	(2,635,000)	(4,670,000)
Other assets and liabilities, net	(4,902,000)	(11,437,000)
Net cash used in operating activities	(290,091,000)	(179,512,000)
Cash flows - investing activities
Acquisition of businesses, net of cash acquired	(35,749,000)	0
Capital expenditures	(6,814,000)	(4,236,000)
Purchases of marketable securities and investments	(27,683,000)	(5,358,000)
Proceeds from sales of marketable securities and investments	268,118,000	990,000
Net cash provided by (used in) investing activities	197,872,000	(8,604,000)
Cash flows - financing activities
Repurchases of common stock	(904,000)	0
Cash dividends paid	(6,234,000)	(6,223,000)
Payment of employee tax withholdings on equity transactions	(4,141,000)	(3,219,000)
Acquisition earnout payments	(35,946,000)	0
Net cash used in financing activities	(47,225,000)	(9,442,000)
Effect of exchange rate fluctuations on cash, cash equivalents and restricted cash	1,772,000	(11,051,000)
Net decrease in cash, cash equivalents and restricted cash	(137,672,000)	(208,609,000)
Cash, cash equivalents and restricted cash at beginning of period	355,489,000	545,259,000
Cash, cash equivalents and restricted cash at end of period	$ 217,817,000	$ 336,650,000