Loans and Allowance for Credit Losses - Aging in past due loans and nonaccrual status, with and without an ACL, by loan segment (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL	$ 8,378	$ 919
Totals	3,685,590	3,724,282
Current
Aging of the recorded investment in past due loans by loan segment
Totals	3,677,147	3,708,253
30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Totals	65	15,110
Commercial
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL		95
Totals	493,403	464,061
Commercial \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	493,338	463,966
Commercial \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Totals	65
Construction and Land Development
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL	64	80
Totals	118,596	232,804
Construction and Land Development \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	118,532	232,724
1-4 Family Construction
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL		249
Totals	45,822	65,087
1-4 Family Construction \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	45,822	64,838
1-4 Family Mortgage
Aging of the recorded investment in past due loans by loan segment
Totals	421,179	402,396
1-4 Family Mortgage \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	421,179	402,396
Multifamily
Aging of the recorded investment in past due loans by loan segment
Totals	1,379,814	1,388,541
Multifamily \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	1,379,814	1,373,431
Multifamily \| 30-89 Days Past Due
Aging of the recorded investment in past due loans by loan segment
Totals		15,110
CRE Owner Occupied
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL		494
Totals	182,239	175,783
CRE Owner Occupied \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	182,239	175,289
CRE Non-owner Occupied
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL	8,314
Totals	1,032,142	987,306
CRE Non-owner Occupied \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	1,023,828	987,306
Consumer and other
Aging of the recorded investment in past due loans by loan segment
Nonaccrual without ACL		1
Totals	12,395	8,304
Consumer and other \| Current
Aging of the recorded investment in past due loans by loan segment
Totals	$ 12,395	$ 8,303

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-14

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 80
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-80

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