Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets
Allowance for expected credit losses	$ 1,213	$ 1,404
Accrued paid time off	3,039	2,801
Foreign net operating loss carry forward		229
State net operating loss carry forward	500	502
Stock based compensation	5,523	1,586
Deferred compensation	5,765	4,692
Foreign tax credits	8,035	7,236
Federal and state tax credits	686	384
Foreign exchange	3,591	4,532
Foreign deferred	441	875
Accrued bonus	5,830	5,696
Capital loss	1,054
Facilities impairment	3,092	2,650
Capitalized research expenses	47,019	990
Accrued liabilities and other	2,682	5,523
Lease liabilities	58,538	56,695
Deferred Tax Assets, gross, before valuation allowance	147,008	95,795
Less: Valuation Allowance	(9,021)	(7,607)	$ (7,048)	$ (6,839)
Total Deferred Tax Assets	137,987	88,188
Deferred Tax Liabilities
Retention		(407)
Prepaid expenses		(366)
Payroll taxes	(725)	(697)
Unbilled revenue	(284)	(409)
Depreciation	(2,128)	(270)
Amortization	(107,201)	(99,045)
Deferred gain and other	(2,202)	(2,561)
Lease assets - Right-of-Use	(51,622)	(52,471)
Total Deferred Tax Liabilities	(164,162)	(156,226)
Total Net Deferred Tax Liability	$ (26,175)	$ (68,038)