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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Summary of Significant Accounting Policies (Details) - Parent Company - USD ($) $ / shares in Units, $ in Millions	Jul. 02, 2026	Jan. 15, 2026	Jul. 03, 2026
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)		100
Sale of stock, price per share (in dollars per share)		$ 0.10
Subsequent Event \| ITG Parent
Class of Stock [Line Items]
Investment owned, balance, shares (in shares)	22,439,025
Ownership percentage	39.02%		25.57%
Subsequent Event \| IPO
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	22,439,025
Sale of stock, price per share (in dollars per share)	$ 16.00
Sale of stock, consideration received on transaction	$ 338.4