Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 217,776	$ 355,447
Marketable securities	21,240	266,169
Accounts receivable, net of allowances of $6,979 and $6,643, respectively	197,899	126,437
Prepaid expenses	27,401	24,098
Other current assets	50,622	40,722
Income taxes recoverable	8,397	10,946
Total current assets	523,335	823,819
Non-current assets
Property and equipment, net	33,330	30,207
Operating lease right-of-use assets	69,692	71,457
Assets designated for retirement and pension plans	11,552	11,332
Investments	44,357	34,354
Other non-current assets	22,082	25,788
Goodwill	198,639	138,361
Other intangible assets, net	26,903	6,333
Deferred income taxes	34,565	33,987
Total non-current assets	441,120	351,819
Total assets	964,455	1,175,638
Current liabilities
Accounts payable	15,477	14,613
Accrued salaries and benefits	193,858	451,161
Deferred revenue	44,102	43,057
Operating lease liabilities	21,221	19,554
Other current liabilities	36,017	56,016
Income taxes payable	8,118	4,076
Total current liabilities	318,793	588,477
Non-current liabilities
Accrued salaries and benefits	48,444	59,467
Retirement and pension plans	58,951	48,456
Operating lease liabilities	60,326	63,299
Other non-current liabilities	42,005	5,293
Deferred income taxes	7,619	0
Total non-current liabilities	217,345	176,515
Total liabilities	536,138	764,992
Commitments and contingencies (Note 18)
Stockholders’ equity
Preferred stock, $0.01 par value, 10,000,000 shares authorized, no shares issued at June 30, 2023 and December 31, 2022	0	0
Common stock, $0.01 par value, 100,000,000 shares authorized, 20,037,959 and 19,866,287 shares issued, 20,007,771 and 19,861,207 shares outstanding at June 30, 2023 and December 31, 2022, respectively	200	199
Treasury stock at cost, 30,188 and 5,080 shares at June 30, 2023 and December 31, 2022, respectively	(819)	(191)
Additional paid in capital	246,226	246,630
Retained earnings	186,531	168,197
Accumulated other comprehensive loss	(3,821)	(4,189)
Total stockholders’ equity	428,317	410,646
Total liabilities and stockholders’ equity	$ 964,455	$ 1,175,638