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Commitments and Contingencies (Narrative) (Details) $ in Thousands		12 Months Ended
	Jan. 14, 2022 lawsuit	Dec. 31, 2021 USD ($) lawsuit	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Rent expense | $		$ 11,190	$ 9,711	$ 10,159
Sandford Trust Company Litigation, Federal Class Actions
Loss Contingencies [Line Items]
Number of dismissed actions		2
Stanford Trust Company Litigation, Ancillary Actions
Loss Contingencies [Line Items]
Number of actions filed		5
Number of pending actions		3
Stanford Trust Company Litigation, Ancillary Actions | Subsequent Event
Loss Contingencies [Line Items]
Number of dismissed actions	2
Stanford Trust Company Litigation, Farr and Rolland
Loss Contingencies [Line Items]
Number of pending actions		2
User licenses for software
Loss Contingencies [Line Items]
Rent expense | $		$ 57,880	$ 41,091	$ 33,600

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Amount of operating lease expense. Excludes sublease income.

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