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Basis of Presentation and Recent Developments (Details) € in Millions, ₪ in Millions, £ in Millions, R$ in Millions, $ in Millions													3 Months Ended			12 Months Ended
	Oct. 01, 2024 USD ($) shares	Jul. 19, 2024 USD ($) shares	Jul. 19, 2024 ILS (₪) shares	Apr. 05, 2024 USD ($) shares	Apr. 05, 2024 BRL (R$) shares	Apr. 04, 2024 USD ($)	Apr. 04, 2024 EUR (€)	Mar. 01, 2024 USD ($) shares	Mar. 01, 2024 GBP (£) shares	Jan. 02, 2024 USD ($) shares	Nov. 01, 2023 USD ($) shares	Oct. 02, 2023 USD ($) shares	Sep. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023	Nov. 06, 2024 USD ($)	Jul. 19, 2024 ILS (₪)	Apr. 05, 2024 BRL (R$)	Apr. 04, 2024 EUR (€)	Mar. 01, 2024 GBP (£)
Business Acquisition [Line Items]
Income Tax Expense Adjustment													$ 10.4	$ 5.3	$ 7.3
Income Tax Expense Adjustment													$ 10.4	$ 5.3	$ 7.3
Subsequent event
Business Acquisition [Line Items]
Stock Repurchase Program, Authorized Amount																	$ 375.0
Stock Repurchase Program, Increase in Authorized Amount																	125.0
Stock Repurchase Program, Authorized Amount																	375.0
Stock Repurchase Program, Increase in Authorized Amount																	$ 125.0
income tax expense
Business Acquisition [Line Items]
Immaterial Error Correction																2.1 million
Income tax receivable and payable
Business Acquisition [Line Items]
Immaterial Error Correction														12.9 million
Accumulated Other Comprehensive Income (Loss), Net of Tax
Business Acquisition [Line Items]
Immaterial Error Correction																23.5 million
Income tax payable
Business Acquisition [Line Items]
Immaterial Error Correction																2.4 million
Deferred tax asset
Business Acquisition [Line Items]
Immaterial Error Correction																4.5 million
Tax receivable agreement
Business Acquisition [Line Items]
Immaterial Error Correction													2.1 million
Left Field Labs
Business Acquisition [Line Items]
Aggregate purchase price												$ 13.2
Payments to Acquire Businesses, Gross												$ 9.4
Shares issued by the Company (shares) \| shares												825,402
Deferred acquisition consideration												$ 51.0
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned												$ 3.8
Movers and Shakers LLC
Business Acquisition [Line Items]
Aggregate purchase price											$ 14.7
Payments to Acquire Businesses, Gross											10.2
Deferred acquisition consideration											35.0
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned											$ 4.5
Movers and Shakers LLC \| Common Class A
Business Acquisition [Line Items]
Shares issued by the Company (shares) \| shares											1,000,000
Team Epiphany
Business Acquisition [Line Items]
Aggregate purchase price										$ 15.8
Payments to Acquire Businesses, Gross										$ 10.8
Shares issued by the Company (shares) \| shares										797,916
Deferred acquisition consideration										$ 17.0
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned										$ 5.0
Sidekick Live Limited
Business Acquisition [Line Items]
Aggregate purchase price								$ 6.0	£ 4.6
Payments to Acquire Businesses, Gross								$ 5.0	£ 3.6
Shares issued by the Company (shares) \| shares								195,431	195,431
Deferred acquisition consideration								$ 10.0													£ 8.0
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned								$ 1.0													£ 0.9
What's Next Partners
Business Acquisition [Line Items]
Aggregate purchase price						$ 5.0	€ 4.3
Deferred acquisition consideration						$ 9.0														€ 8.5
PROS Agency
Business Acquisition [Line Items]
Aggregate purchase price				$ 9.0	R$ 42.1
Payments to Acquire Businesses, Gross				$ 5.0	R$ 23.3
Shares issued by the Company (shares) \| shares				182,256	182,256
Deferred acquisition consideration				$ 3.0															R$ 13.5
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned				$ 1.0															R$ 5.3
Leaders
Business Acquisition [Line Items]
Aggregate purchase price		$ 7.0	₪ 25.2
Payments to Acquire Businesses, Gross		$ 3.0	₪ 10.9
Shares issued by the Company (shares) \| shares		135,010	135,010
Deferred acquisition consideration		$ 3.0																₪ 10.9
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned		$ 1.0																₪ 3.5
Consulum \| Subsequent event
Business Acquisition [Line Items]
Aggregate purchase price	$ 71.2
Payments to Acquire Businesses, Gross	$ 58.3
Shares issued by the Company (shares) \| shares	1,810,274
Deferred acquisition consideration	$ 90.0
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 12.9