Acquisitions - Recognized Identified Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Apr. 01, 2023	Dec. 31, 2022
Assets:
Goodwill	$ 397,098		$ 348,836
AlphaSimplex Group, LLC
Assets:
Cash and cash equivalents		$ 4,395
Investments		8,567
Accounts receivable		5,422
Furniture, equipment and leasehold improvements		4,161
Intangible assets		55,400
Goodwill		48,262
Other assets		9,126
Total Assets		135,333
Liabilities:
Accounts payable and accrued liabilities		21,939
Total Liabilities		21,939
Total Net Assets Acquired		$ 113,394