Bank Loans (Activity In The Allowance For Loan Losses By Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 104,198	$ 107,668	$ 99,344	$ 112,029
Provision	3,318	(4,204)	8,172	(7,631)
Charge-offs	36	(4,268)	36	5,202
Recoveries	2	0	2	0
Ending Balance	107,482	99,196	107,482	99,196
Commercial and Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	54,580	56,316	53,529	67,222
Provision	12,770	(5,105)	13,821	(15,077)
Charge-offs		(4,268)		5,202
Recoveries	2	0	2	0
Ending Balance	67,352	46,943	67,352	46,943
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	32,927	16,665	28,560	16,300
Provision	(10,312)	4,602	(5,945)	4,967
Ending Balance	22,615	21,267	22,615	21,267
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	8,121	18,873	8,536	17,275
Provision	(2,267)	(2,920)	(2,682)	(1,322)
Ending Balance	5,854	15,953	5,854	15,953
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	3,976	2,169	4,006	2,015
Provision	36	350	6	504
Charge-offs	36		36
Ending Balance	3,976	2,519	3,976	2,519
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	3,680	13,060	3,934	8,580
Provision	2,803	(1,157)	2,549	3,323
Ending Balance	6,483	11,903	6,483	11,903
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	683	341	511	374
Provision	239	85	411	52
Recoveries		0		0
Ending Balance	922	426	922	426
Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	231	244	268	263
Provision	49	(59)	12	(78)
Charge-offs		0		0
Recoveries		0		0
Ending Balance	$ 280	$ 185	$ 280	$ 185