Related Party Transactions - Schedule of Balances From Transactions with Affiliates Included in the Consolidated Statements (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Related Party Transactions
Accounts receivable	$ 309,368	$ 257,845
Receivable and due from related parties	7,016	8,303
Other assets	237,582	140,249
Deferred revenue	38,368	29,030
Payable and due to related parties	11,160	7,090
Equity method investments	23,700	4,500
iAltaA Capital Markets, LLC
Related Party Transactions
Equity method investments	$ 3,600	4,500
Equity method investment percentage	50.00%
Other Equity Investments
Related Party Transactions
Equity method investments	$ 40,200
Affiliated Entity
Related Party Transactions
Accounts receivable	20	56
Receivable and due from related parties	7,016	8,303
Other assets	43,758	4,472
Deferred revenue	7,950	0
Payable and due to related parties	$ 11,160	$ 7,090
Affiliated Entity \| iAltaA Capital Markets, LLC
Related Party Transactions
Equity method investment percentage	50.00%

Account receivable excluding receivable from brokers and dealers and clearing organizations, net of allowance.

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