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Significant Transactions - Distinguished Programs (Details) - USD ($) $ in Millions			3 Months Ended
	Nov. 01, 2025	Sep. 02, 2025	Mar. 31, 2026	Dec. 31, 2025
Distinguished
Other Significant Transactions [Line Items]
Basic units outstanding percentage		31.40%
Subsidiary - Distinguished Managing General Agent
Other Significant Transactions [Line Items]
Basic ownership		55.50%	55.50%	55.50%
Business combination, basic ownership interest acquired, percentage		1.70%
Ownership percentage, fully diluted		43.60%	43.60%	43.60%
Subsidiary, ownership percentage economic interest falls		50.00%
Subsidiary - Distinguished Managing General Agent \| Distinguished Management
Other Significant Transactions [Line Items]
Ownership percentage, fully diluted		24.70%
Ownership percentage of basic units outstanding		4.20%
Distinguished Transaction
Other Significant Transactions [Line Items]
Business combination, consideration transferred		$ 224.8
Post-closing purchase price adjustment		0.5
Business combination, consideration transferred, liabilities incurred		50.0
Cash on hand		$ 6.8
Redemption value			$ 131.5
Business combination, right to purchase units		1.35
Assets and goodwill acquired		$ 745.1
Goodwill		620.0
Liabilities acquired		250.9
Redeemable noncontrolling interest		133.5
Nonredeemable noncontrolling interest		73.8
Goodwill, intangible assets and other liabilities acquired, measurement period adjustment			$ 1.2
Transaction costs		6.8
Other intangible assets		$ 198.2
Distinguished Transaction, ScaleCo Program
Other Significant Transactions [Line Items]
Business combination, consideration transferred	$ 33.6
Acquisition of businesses	23.6
Other intangible assets	$ 9.3