Loans - Financing Receivable, Gross Charge-Offs By Year of Origination (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 1,208,188		$ 1,208,188
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	719,078		719,078
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	667,895		667,895
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	391,455		391,455
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	321,844		321,844
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	342,978		342,978
Financing Receivable, Revolving	2,486,421		2,486,421
Financing Receivable, Allowance for Credit Loss, Writeoff	4,282	$ 7,136	6,426	$ 13,316
Commercial and Industrial Total Energy Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	304,570		304,570
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	36,014		36,014
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	55,059		55,059
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	50,104		50,104
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,055		4,055
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	10,415		10,415
Financing Receivable, Revolving	628,754		628,754
Financing Receivable, Allowance for Credit Loss, Writeoff	79	518	79	518
Commercial Real Estate Buildings Land And Other Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	690,654		690,654
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,490,259		1,490,259
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,708,392		1,708,392
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,234,202		1,234,202
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	751,974		751,974
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,296,706		1,296,706
Financing Receivable, Revolving	167,257		167,257
Financing Receivable, Allowance for Credit Loss, Writeoff			122
Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	351,397		351,397
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	516,044		516,044
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	647,171		647,171
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	298,063		298,063
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	28,003		28,003
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,296		1,296
Financing Receivable, Revolving	155,406		155,406
Financing Receivable, Allowance for Credit Loss, Writeoff			0
Total consumer real estate loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	408	1,080	2,077	1,330
Consumer Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	8,360	7,016	16,617	13,958
Loans Receivable [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff	13,251	$ 15,750	25,321	$ 29,122
Nonperforming Financial Instruments [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	5,596		5,596
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	23,879		23,879
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	4,186		4,186
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	8,440		8,440
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	570		570
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	11,348		11,348
Financing Receivable, Revolving	8,088		8,088
Financing Receivable, Revolving, Converted to Term Loan	12,880		12,880
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	746		746
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,764		3,764
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,159		1,159
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	3,066		3,066
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	514		514
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,197		2,197
Financing Receivable, Revolving	2,149		2,149
Financing Receivable, Revolving, Converted to Term Loan	12,734		12,734
Nonperforming Financial Instruments [Member] | Commercial and Industrial Total Energy Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	4,522		4,522
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	56		56
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,321		1,321
Financing Receivable, Revolving	3,102		3,102
Financing Receivable, Revolving, Converted to Term Loan	146		146
Nonperforming Financial Instruments [Member] | Commercial Real Estate Buildings Land And Other Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	328		328
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,115		20,115
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	3,027		3,027
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	5,374		5,374
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,411		1,411
Financing Receivable, Revolving	2,837		2,837
Financing Receivable, Revolving, Converted to Term Loan	0		0
Nonperforming Financial Instruments [Member] | Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	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]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	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	6,419		6,419
Financing Receivable, Revolving	0		0
Financing Receivable, Revolving, Converted to Term Loan	0		0
Nonperforming Financial Instruments [Member] | Consumer Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	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
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	9,369		9,369
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	6,263		6,263
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,077		1,077
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	724		724
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	405		405
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,060		1,060
Financing Receivable, Revolving	5,459		5,459
Financing Receivable, Revolving, Converted to Term Loan	964		964
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	471		471
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	676		676
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	467		467
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	401		401
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	625		625
Financing Receivable, Revolving	2,902		2,902
Financing Receivable, Revolving, Converted to Term Loan	884		884
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Commercial and Industrial Total Energy Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	79		79
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
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Commercial Real Estate Buildings Land And Other Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	122		122
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
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	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
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Total consumer real estate loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0		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	148		148
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	253		253
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	384		384
Financing Receivable, Revolving	1,225		1,225
Financing Receivable, Revolving, Converted to Term Loan	67		67
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] | Consumer Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	9,369		9,369
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	5,713		5,713
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	131		131
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4		4
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4		4
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	51		51
Financing Receivable, Revolving	1,332		1,332
Financing Receivable, Revolving, Converted to Term Loan	$ 13		$ 13