Loans Loans - Non-Accrual Loans, Segregated by Class of Loans and Year of Origination (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loans and Leases Receivable Disclosure [Line Items]
Non-accrual loans	$ 38,410	$ 37,833
Nonperforming Financial Instruments [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	7,812
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	6,843
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,587
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	919
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,703
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,903
Financing Receivable, Revolving	7,909
Financing Receivable, Revolving, Converted to Term Loan	5,734
Commercial Portfolio Segment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	828,110
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,039,545
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	624,808
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	448,505
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	220,055
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	300,049
Financing Receivable, Revolving	2,133,845
Non-accrual loans	10,494	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	139
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,026
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	815
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	3,121
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,247
Financing Receivable, Revolving	690
Financing Receivable, Revolving, Converted to Term Loan	3,456
Commercial and Industrial Total Energy Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	325,616
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	88,754
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	94,011
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,887
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	8,100
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	9,311
Financing Receivable, Revolving	491,780
Non-accrual loans	22,349	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	7,812
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,161
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	72
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,371
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	8
Financing Receivable, Revolving	7,219
Financing Receivable, Revolving, Converted to Term Loan	1,706
Commercial Real Estate Buildings Land And Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	447,974
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,766,241
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,482,017
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	968,630
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	676,887
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,186,720
Financing Receivable, Revolving	154,539
Non-accrual loans	4,604	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	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,543
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	303
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	211
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,547
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	214,583
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	553,934
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	427,754
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	101,526
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	961
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,970
Financing Receivable, Revolving	180,876
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	963	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	258
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	32
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	101
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted to Term Loan	572
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
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