Bank Loans (Aging Of The Recorded Investment In Past Due Loans) (Details) - USD ($)		Jun. 30, 2022		Dec. 31, 2021
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 19,331,000		$ 23,432,000
Total		19,158,620,000		16,743,487,000
Non-Accrual		29,156,000	[1]	17,193,000	[2]
Restructured		153,000	[1]	154,000	[2]
Nonperforming loans with no allowance		0	[1]	1,000	[2]
Total		29,309,000	[1]	17,348,000	[2]
Loans past due 90 days and still accruing interest		0		0
Non-Accrual		29,156,000	[1]	17,193,000	[2]
30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		2,159,000		15,528,000
90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		17,172,000		7,904,000
Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		19,139,289,000		16,720,055,000
Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		3,237,000		7,526,000
Total		6,607,825,000		5,482,026,000
Non-Accrual		1,790,000	[1]	1,332,000	[2]
Restructured		153,000	[1]	154,000	[2]
Nonperforming loans with no allowance	[2]			0
Total		1,943,000	[1]	1,486,000	[2]
Non-Accrual		1,790,000	[1]	1,332,000	[2]
Residential Real Estate [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		1,447,000		6,194,000
Residential Real Estate [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		1,790,000		1,332,000
Residential Real Estate [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		6,604,588,000		5,474,500,000
Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		15,368,000		15,861,000
Total		8,347,410,000		7,345,753,000
Non-Accrual		27,352,000	[1]	15,861,000	[2]
Total		27,352,000	[1]	15,861,000	[2]
Non-Accrual		27,352,000	[1]	15,861,000	[2]
Commercial and Industrial [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due				9,290,000
Commercial and Industrial [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		15,368,000		6,571,000
Commercial and Industrial [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		8,332,042,000		7,329,892,000
Securities-Based Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total		2,993,552,000		2,880,158,000
Securities-Based Loans [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		2,993,552,000		2,880,158,000
Commercial Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due				1,000
Total		629,459,000		409,847,000
Non-Accrual	[2]			0
Nonperforming loans with no allowance	[2]			1,000
Total	[2]			1,000
Non-Accrual	[2]			0
Commercial Real Estate [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due				1,000
Commercial Real Estate [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		629,459,000		409,846,000
Home Equity Lines Of Credit [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		699,000		0
Total		103,096,000		82,508,000
Home Equity Lines Of Credit [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		699,000		0
Home Equity Lines Of Credit [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		102,397,000		82,508,000
Construction And Land [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total		432,039,000		511,084,000
Construction And Land [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		432,039,000		511,084,000
Other [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		27,000		44,000
Total		45,239,000		32,111,000
Non-Accrual	[1]	14,000
Total	[1]	14,000
Non-Accrual	[1]	14,000
Other [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		13,000		44,000
Other [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		14,000
Other [Member] | Current Balance [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 45,212,000		$ 32,067,000

[1] There were no loans past due 90 days and still accruing interest at June 30, 2022

[2] There were no loans past due 90 days and still accruing interest at December 31, 2021.