Loans Loans - Non-Accrual Loans, Segregated by Class of Loans and Year of Origination (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	$ 67,175	$ 37,833
Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	26,586
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	464
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	380
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	841
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	7,958
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	3,971
Financing Receivable, Revolving	26,426
Financing Receivable, Revolving, Converted to Term Loan	549
Commercial Portfolio Segment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,391,552
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	877,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	528,835
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	396,428
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	193,707
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	234,603
Financing Receivable, Revolving	2,152,870
Non-accrual loans	27,326	18,130
Commercial Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	359
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	84
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	747
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,812
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,068
Financing Receivable, Revolving	21,924
Financing Receivable, Revolving, Converted to Term Loan	332
Commercial and Industrial Total Energy Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	331,902
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	72,578
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	79,911
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,162
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	7,237
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	4,874
Financing Receivable, Revolving	497,025
Non-accrual loans	14,200	15,224
Commercial and Industrial Total Energy Loans [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	8,148
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	56
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,348
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, Revolving	4,502
Financing Receivable, Revolving, Converted to Term Loan	146
Commercial Real Estate Buildings Land And Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,217,271
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,776,671
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,414,317
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	871,262
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	568,451
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,012,988
Financing Receivable, Revolving	228,252
Non-accrual loans	23,112	3,552
Commercial Real Estate Buildings Land And Other Loans [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	18,438
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	105
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	296
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,463
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,810
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted to Term Loan	0
Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	419,819
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	555,411
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	369,185
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	47,871
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	305
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,638
Financing Receivable, Revolving	150,437
Non-accrual loans	0	0
Construction Loans [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted to Term Loan	0
Total consumer real estate loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	2,537	927
Total consumer real estate loans [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	38
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,335
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	93
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted to Term Loan	71
Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	0	$ 0
Consumer Loan [Member] \| Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted to Term Loan	$ 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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Paragraph 6
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

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