Business Developments and Reorganization (Details) $ / shares in Units, $ in Thousands				9 Months Ended
	May 22, 2026 USD ($)	May 21, 2026 USD ($) class_of_stock $ / shares	May 20, 2026 USD ($)	Sep. 30, 2026 USD ($) vote $ / shares shares	Sep. 30, 2025 USD ($)
Subsidiary or Equity Method Investee [Line Items]
Dividends | $			$ 70,600
Number of classes of common stock | class_of_stock		3
Common stock , issued (in shares)				103,835,628
Common stock, outstanding (in shares)				103,835,628
Common unit not held by the parent (in shares)				67,463,229
Preferred stock, outstanding (in shares)				0
Distributions of IPO proceeds to partners | $		$ 254,500		$ 254,493	$ 0
General Partner
Subsidiary or Equity Method Investee [Line Items]
Payment of IPO proceeds to redeem outstanding units | $	$ 176,300
Limited Partner
Subsidiary or Equity Method Investee [Line Items]
Payment of IPO proceeds to redeem outstanding units | $	$ 68,400
Lincoln International, Partners
Subsidiary or Equity Method Investee [Line Items]
Distributions of IPO proceeds to partners | $		$ 244,700
Class A
Subsidiary or Equity Method Investee [Line Items]
Common stock , issued (in shares)				36,372,399
Common stock, outstanding (in shares)				36,372,399
Common stock, par value (in USD per share) | $ / shares		$ 0.00001		$ 0.00001
Common stock, number of votes per share | vote				1
Requirement of common stock outstanding to LILP common units owned				1
Limited partnership unit to common stock conversion ratio				1
Class B
Subsidiary or Equity Method Investee [Line Items]
Common stock , issued (in shares)				28,596,847
Common stock, outstanding (in shares)				28,596,847
Common stock, par value (in USD per share) | $ / shares				$ 0.00001
Common stock, number of votes per share | vote				1
Class C
Subsidiary or Equity Method Investee [Line Items]
Common stock , issued (in shares)				38,866,382
Common stock, outstanding (in shares)				38,866,382
Common stock, par value (in USD per share) | $ / shares				$ 0.00001
Common stock, number of votes per share | vote				10
Lincoln International, LP
Subsidiary or Equity Method Investee [Line Items]
Ownership interest in outstanding common units, percent		35.00%