Bank Loans (Activity In The Allowance For Loan Losses By Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 128,292	$ 111,653
Provision	4,558	5,376
Charge-offs	(3,570)	(20)
Recoveries	933	153
Ending Balance	130,213	117,162
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	67,077	54,143
Provision	1,447	1,458
Charge-offs	(3,570)	(20)
Recoveries	933	153
Ending Balance	65,887	55,734
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	21,386	12,897
Provision	(697)	(1,331)
Ending Balance	20,689	11,566
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	13,855	20,441
Provision	(1,348)	2,255
Ending Balance	12,507	22,696
Fund Banking [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	10,173	11,711
Provision	(1,410)	1,232
Ending Balance	8,763	12,943
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	11,817	8,568
Provision	6,772	1,749
Ending Balance	18,589	10,317
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	3,035	3,157
Provision	33	(40)
Ending Balance	3,068	3,117
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	371	364
Provision	(125)	48
Ending Balance	246	412
Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	578	372
Provision	(114)	5
Ending Balance	$ 464	$ 377