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Derivative Contracts - Fair Value of Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Not Designated as Hedging Instrument | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 1,585.0	$ 1,802.9	$ 1,675.3
Cash collateral	1.9	3.4	3.7
Not Designated as Hedging Instrument | Derivative Financial Instruments, Assets [Member] | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value	23.8	31.4	41.9
Derivative, Notional Amount	1,064.7	1,262.1	945.8
Not Designated as Hedging Instrument | Derivative liabilities | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value	(3.1)	(9.3)	(3.2)
Derivative, Notional Amount	520.3	540.8	729.5
Not Designated as Hedging Instrument | Derivative liabilities | Embedded Derivative Financial Instruments
Derivatives, Fair Value [Line Items]
Fair Value	(4.6)	(16.5)	(31.7)
Derivative, Notional Amount	0.0	0.0	0.0
Designated as Hedging Instrument | Derivative Financial Instruments, Assets [Member] | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value	2.2	0.3	14.3
Derivative, Notional Amount	$ 40.6	$ 76.9	$ 109.7

X

- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

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X

- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480463/815-10-45-5

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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