Discontinued Operations, Deconsolidation of European Joint Venture, Divestitures and Acquisitions - Schedule of Fair Values of Identifiable Assets and Liabilities of Acquisitions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2024	Dec. 31, 2023
Liabilities
Goodwill arising from acquisitions	$ 724,822	$ 477,021	$ 710,191
2022 Acquisitions
Consideration:
Cash Consideration	74,206
Holdback	810
Fair value of contingent consideration	510
Total consideration	75,526
Identifiable intangible assets	25,546
Assets
Accounts receivable	6,817
Other assets	3,446
Identifiable intangible assets	25,546
Total assets	35,809
Liabilities
Accounts payable	7,363
Deferred tax liabilities and other	8,546
Total liabilities	15,909
Redeemable noncontrolling interest	1,987
Noncontrolling interest	974
Total identifiable net assets	16,939
Goodwill arising from acquisitions	$ 58,587
2022 Acquisitions | Client relationships [Member]
Consideration:
Weighted Average Useful Life	6 years
Identifiable intangible assets	$ 24,413
Assets
Identifiable intangible assets	$ 24,413
2022 Acquisitions | Trade names [Member]
Consideration:
Weighted Average Useful Life	5 years
Identifiable intangible assets	$ 1,133
Assets
Identifiable intangible assets	$ 1,133