Loans (Non-Accrual Loans, Segregated by Class of Loan and Year of Origination) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	$ 37,833	$ 53,713
Commercial Portfolio Segment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,703,185	1,630,524
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	657,039	693,324
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	498,213	392,408
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	241,997	214,163
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	138,541	150,922
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	195,754	143,292
Financing Receivable, Revolving	2,170,182	2,075,632
Non-accrual loans	18,130	22,582
Commercial and Industrial Total Energy Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	352,224	475,023
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	100,862	9,539
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	5,312	20,991
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	8,659	9,480
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	3,078	3,110
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,913	5,638
Financing Receivable, Revolving	408,022	483,020
Non-accrual loans	15,224	14,433
Commercial Real Estate, Buildings, Land and Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,901,888	1,761,554
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,528,173	1,257,055
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,009,197	1,008,366
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	745,031	632,020
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	410,327	612,767
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	882,021	825,249
Financing Receivable, Revolving	120,958	59,595
Non-accrual loans	3,552	15,297
Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	666,024	693,192
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	491,563	268,080
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	130,888	178,226
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	2,236	2,339
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	486	484
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,726	1,930
Financing Receivable, Revolving	181,180	160,020
Non-accrual loans	0	948
Total consumer real estate loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	927	440
Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	0	13
Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	6,301	6,687
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,510	5,111
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,161	13,851
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,845	3,959
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,473	2,795
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,700	3,423
Financing Receivable, Revolving	10,604	11,566
Financing Receivable, Revolving, Converted to Term Loan	10,239	6,321
Nonperforming Financial Instruments [Member] \| Commercial Portfolio Segment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0	636
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,252	3,856
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,089	5,047
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	3,242	1,820
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,197	765
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	191	353
Financing Receivable, Revolving	2,973	4,635
Financing Receivable, Revolving, Converted to Term Loan	8,186	5,470
Nonperforming Financial Instruments [Member] \| Commercial and Industrial Total Energy Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	4,657	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	72	5,358
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,386	1,325
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	10	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0	0
Financing Receivable, Revolving	7,631	6,931
Financing Receivable, Revolving, Converted to Term Loan	1,468	819
Nonperforming Financial Instruments [Member] \| Commercial Real Estate, Buildings, Land and Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,644	6,038
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	307
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0	3,446
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	217	814
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	266	2,030
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,425	2,662
Financing Receivable, Revolving	0	0
Financing Receivable, Revolving, Converted to Term Loan	0	0
Nonperforming Financial Instruments [Member] \| Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	948
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0	0
Financing Receivable, Revolving	0	0
Financing Receivable, Revolving, Converted to Term Loan	0	0
Nonperforming Financial Instruments [Member] \| Total consumer real estate loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	258	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	84	408
Financing Receivable, Revolving	0	0
Financing Receivable, Revolving, Converted to Term Loan	585	32
Nonperforming Financial Instruments [Member] \| Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0	13
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0	0
Financing Receivable, Revolving	0	0
Financing Receivable, Revolving, Converted to Term Loan	$ 0	$ 0

Amortized cost of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 55
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