Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Operating Activities:
Net earnings	$ 229,926	$ 170,843	$ 575,477	$ 592,634
Adjustments to reconcile net earnings to net cash from operating activities:
Provisions for (recoveries) losses on accounts receivable	(582)	1,411	1,456	2,316
Deferred income tax benefit	(1,057)	(6,418)	(5,680)	(7,942)
Stock compensation expense	9,760	15,879	47,836	46,962
Depreciation and amortization	15,774	15,607	45,914	46,374
Other, net	162	2,673	4,032	6,396
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	(301,167)	(53,722)	(647,794)	629,205
Increase (decrease) in accounts payable and accrued liabilities	107,535	40,919	402,818	(311,990)
(Increase) decrease in deferred contract costs	(30,657)	(56,917)	(216,977)	28,870
Increase (decrease) in contract liabilities	50,527	74,701	254,902	(33,549)
Increase (decrease) in income taxes payable, net	20,331	(4,017)	13,163	(97,743)
Increase in other, net	(10,580)	(10,979)	(1,502)	(6,695)
Net cash from operating activities	89,972	189,980	473,645	894,838
Investing Activities:
Purchase of property and equipment	(12,291)	(7,993)	(30,415)	(28,600)
Other, net	(225)	10	(62)	(209)
Net cash from investing activities	(12,516)	(7,983)	(30,477)	(28,809)
Financing Activities:
Proceeds from borrowings on lines of credit	10,636	8,404	14,762	26,953
Payments on borrowings on lines of credit	(191)	(1,491)	(20,300)	(33,636)
Proceeds from issuance of common stock	53,256	61,841	67,734	80,305
Repurchases of common stock	(140,031)	(298,103)	(602,855)	(1,199,294)
Dividends paid	0	0	(102,638)	(102,263)
Payments for taxes related to net share settlement of equity awards	0	0	(15,348)	(19,501)
Net cash from financing activities	(76,330)	(229,349)	(658,645)	(1,247,436)
Effect of exchange rate changes on cash and cash equivalents	20,194	(11,807)	(4,233)	(13,296)
Change in cash and cash equivalents	21,320	(59,159)	(219,710)	(394,703)
Cash and cash equivalents at beginning of period	1,271,853	1,698,587	1,512,883	2,034,131
Cash and cash equivalents at end of period	1,293,173	1,639,428	1,293,173	1,639,428
Taxes Paid:
Income taxes	$ 63,046	$ 61,603	$ 196,649	$ 306,059