Amortization period for pushdown accounting adjustments.

No definition available.

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- Definition

Amount of accumulated depreciation, depletion, and amortization of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

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- Definition

Amount of amortization expense for finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Useful life of finite-lived intangible asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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- Definition

Amount of accumulated amortization of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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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.

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Useful life of property, plant, and equipment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

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Significant Accounting Policies - Furniture, Equipment, Purchased Software, Leasehold Improvements and Software Development Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Furniture, Equipment, Purchased Software and Leasehold Improvements
Accumulated depreciation and amortization	$ 104.3		$ 104.3		$ 96.7
Depreciation expense	$ 7.2	$ 5.9	$ 14.4	$ 12.0
Internal software
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	3 years		3 years
Amortization of pushdown accounting allocation			9 years
Accumulated amortization	$ 436.6		$ 436.6		387.1
Amortization expense	$ 25.2	22.6	$ 49.6	44.5
Internal software \| ICD Acquisition
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	8 years		8 years
Internal software \| R8Fin
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	7 years		7 years
Internal software \| Yieldbroker Acquisition
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	1 year		1 year
Internal software \| NFI Acquisition
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	1 year		1 year
Intangible assets excluding internally developed software
Furniture, Equipment, Purchased Software and Leasehold Improvements
Accumulated amortization	$ 857.9		$ 857.9		$ 799.7
Amortization expense	$ 29.1	$ 34.6	$ 58.2	$ 69.2
Minimum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life	3 years		3 years
Minimum \| Intangible assets excluding internally developed software
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	4 years		4 years
Maximum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life	7 years		7 years
Maximum \| Intangible assets excluding internally developed software
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets	15 years		15 years