Loans and Allowance for Credit Losses - Non-Accrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	$ 679,232	$ 1,502,872
Fiscal Year Before Latest Fiscal Year	1,402,306	980,869
Two Years Before Latest Fiscal Year	763,577	457,711
Three Years Before Latest Fiscal Year	389,046	253,347
Four Years Before Latest Fiscal Year	233,488	177,797
Five Or More Years Before Latest Fiscal Year	239,006	156,029
Revolving loans	1,898,134	1,664,787
Revolving loans converted to term loans	191,810	179,317
Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	2,583
Two Years Before Latest Fiscal Year	2,448	0
Three Years Before Latest Fiscal Year	230	6
Four Years Before Latest Fiscal Year	0	1,383
Five Or More Years Before Latest Fiscal Year	0	12
Revolving loans	8,971	7,097
Revolving loans converted to term loans	1,218	191
Total non-accrual loans	12,867	11,272
Nonaccrual Loans with no related Allowance	10,265	11,272
Commercial And Industrial [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	296,217	468,784
Fiscal Year Before Latest Fiscal Year	312,719	305,002
Two Years Before Latest Fiscal Year	223,285	72,154
Three Years Before Latest Fiscal Year	62,743	54,732
Four Years Before Latest Fiscal Year	45,880	55,665
Five Or More Years Before Latest Fiscal Year	44,533	21,045
Revolving loans	1,009,802	957,254
Revolving loans converted to term loans	62,733	40,296
Commercial And Industrial [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	104
Two Years Before Latest Fiscal Year	0	0
Three Years Before Latest Fiscal Year	57	6
Four Years Before Latest Fiscal Year	0	1,383
Five Or More Years Before Latest Fiscal Year	0	12
Revolving loans	8,503	6,479
Revolving loans converted to term loans	1,033	0
Total non-accrual loans	9,593	7,984
Nonaccrual Loans with no related Allowance	6,991	7,984
Energy [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	7,585
Fiscal Year Before Latest Fiscal Year	7,278	306
Two Years Before Latest Fiscal Year	105	228
Three Years Before Latest Fiscal Year	192	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	225,145	164,928
Revolving loans converted to term loans	143	171
Energy [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	0
Two Years Before Latest Fiscal Year	0	0
Three Years Before Latest Fiscal Year	0	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	468	618
Revolving loans converted to term loans	0	0
Total non-accrual loans	468	618
Nonaccrual Loans with no related Allowance	468	618
Commercial Real Estate - Owner-Occupied [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	53,536	96,987
Fiscal Year Before Latest Fiscal Year	83,762	134,092
Two Years Before Latest Fiscal Year	140,184	57,462
Three Years Before Latest Fiscal Year	59,992	50,950
Four Years Before Latest Fiscal Year	51,279	28,241
Five Or More Years Before Latest Fiscal Year	42,435	24,080
Revolving loans	72,630	28,814
Revolving loans converted to term loans	39,009	16,493
Commercial Real Estate - Owner-Occupied [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	0
Two Years Before Latest Fiscal Year	0	0
Three Years Before Latest Fiscal Year	0	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	0	0
Revolving loans converted to term loans	0	0
Total non-accrual loans	0	0
Nonaccrual Loans with no related Allowance	0	0
Commercial Real Estate - Non-Owner-Occupied [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	302,153	843,896
Fiscal Year Before Latest Fiscal Year	915,464	452,692
Two Years Before Latest Fiscal Year	308,924	200,811
Three Years Before Latest Fiscal Year	147,431	101,909
Four Years Before Latest Fiscal Year	95,898	56,354
Five Or More Years Before Latest Fiscal Year	84,853	76,046
Revolving loans	535,819	460,726
Revolving loans converted to term loans	89,740	122,166
Commercial Real Estate - Non-Owner-Occupied [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	2,479
Two Years Before Latest Fiscal Year	2,448	0
Three Years Before Latest Fiscal Year	173	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	0	0
Revolving loans converted to term loans	0	0
Total non-accrual loans	2,621	2,479
Nonaccrual Loans with no related Allowance	2,621	2,479
Residential Real Estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	19,319	77,703
Fiscal Year Before Latest Fiscal Year	76,723	87,430
Two Years Before Latest Fiscal Year	90,458	124,413
Three Years Before Latest Fiscal Year	118,546	45,491
Four Years Before Latest Fiscal Year	40,186	37,395
Five Or More Years Before Latest Fiscal Year	67,055	34,852
Revolving loans	26,962	31,892
Revolving loans converted to term loans	185	191
Residential Real Estate [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	0
Two Years Before Latest Fiscal Year	0	0
Three Years Before Latest Fiscal Year	0	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	0	0
Revolving loans converted to term loans	185	191
Total non-accrual loans	185	191
Nonaccrual Loans with no related Allowance	185	191
Consumer [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	8,007	7,917
Fiscal Year Before Latest Fiscal Year	6,360	1,347
Two Years Before Latest Fiscal Year	621	2,643
Three Years Before Latest Fiscal Year	142	265
Four Years Before Latest Fiscal Year	245	142
Five Or More Years Before Latest Fiscal Year	130	6
Revolving loans	27,776	21,173
Revolving loans converted to term loans	0	0
Consumer [Member] \| Non-Accrual [Member]
Financing Receivable, Nonaccrual [Line Items]
Current Fiscal Year	0	0
Fiscal Year Before Latest Fiscal Year	0	0
Two Years Before Latest Fiscal Year	0	0
Three Years Before Latest Fiscal Year	0	0
Four Years Before Latest Fiscal Year	0	0
Five Or More Years Before Latest Fiscal Year	0	0
Revolving loans	0	0
Revolving loans converted to term loans	0	0
Total non-accrual loans	0	0
Nonaccrual Loans with no related Allowance	$ 0	$ 0

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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