The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Bank Loans (Recorded Balances Of Loans and Amount Of Allowance Allocated Based Upon Impairment Method by Portfolio Segment) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 8,182		$ 8,182
Allowance for Loan Losses, Collectively Evaluated for Impairment	105,931		87,397
Allowance for Loan Losses, Total	114,113	$ 115,821	95,579	$ 91,360	$ 90,472	$ 85,833
Recorded Investment in Loans, Individually Evaluated for Impairment	14,493		14,587
Recorded Investment in Loans, Collectively Evaluated for Impairment	10,739,195		9,738,029
Recorded Investment in Loans, Total	10,753,688		9,752,616
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	8,158		8,158
Allowance for Loan Losses, Collectively Evaluated for Impairment	67,651		61,791
Allowance for Loan Losses, Total	75,809	65,503	69,949	68,172	69,263	68,367
Recorded Investment in Loans, Individually Evaluated for Impairment	13,084		12,991
Recorded Investment in Loans, Collectively Evaluated for Impairment	4,067,855		3,425,962
Recorded Investment in Loans, Total	4,080,939		3,438,953
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	24		24
Allowance for Loan Losses, Collectively Evaluated for Impairment	17,659		14,229
Allowance for Loan Losses, Total	17,683	24,043	14,253	12,562	12,042	11,228
Recorded Investment in Loans, Individually Evaluated for Impairment	1,409		1,412
Recorded Investment in Loans, Collectively Evaluated for Impairment	3,803,427		3,308,136
Recorded Investment in Loans, Total	3,804,836		3,309,548
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,902		2,361
Allowance for Loan Losses, Total	1,902	1,807	2,361	2,181	2,311	1,978
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,841,516		2,098,211
Recorded Investment in Loans, Total	1,841,516		2,098,211
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	7,917		3,564
Allowance for Loan Losses, Total	7,917	10,647	3,564	2,903	2,478	1,778
Recorded Investment in Loans, Collectively Evaluated for Impairment	386,957		428,549
Recorded Investment in Loans, Total	386,957		428,549
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	10,186		4,613
Allowance for Loan Losses, Total	10,186	13,075	4,613	3,267	2,402	1,241
Recorded Investment in Loans, Collectively Evaluated for Impairment	532,319		398,839
Recorded Investment in Loans, Total	532,319		398,839
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	381		442
Allowance for Loan Losses, Total	381	499	442	435	421	310
Recorded Investment in Loans, Individually Evaluated for Impairment			184
Recorded Investment in Loans, Collectively Evaluated for Impairment	67,386		51,021
Recorded Investment in Loans, Total	67,386		51,205
Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	235		194
Allowance for Loan Losses, Total	235	$ 247	194	195	179	88
Recorded Investment in Loans, Collectively Evaluated for Impairment	39,735		27,311
Recorded Investment in Loans, Total	$ 39,735		27,311
Unallocated [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment			203
Allowance for Loan Losses, Total			$ 203	$ 1,645	$ 1,376	$ 843