Loans and Allowance for Credit Losses - Schedule of Activity in Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	$ 27,795	$ 27,609	$ 32,653	$ 31,738
(Charge-offs)/ Recoveries	56	3,259	79	1,351
(Payments)/ Disbursements	(669)	(7,343)	(4,378)	(9,564)
(Removals)/ Additions	2,073	5,907	901	5,907
Ending Balance	29,255	29,432	29,255	29,432
Commercial
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	8,264	10,598	11,090	12,412
(Charge-offs)/ Recoveries	1	1,326	1	632
(Payments)/ Disbursements	(156)	(3,168)	(1,810)	(4,288)
(Removals)/ Additions	2,073	0	901	0
Ending Balance	10,182	8,756	10,182	8,756
Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	15,970	12,706	17,606	14,277
(Charge-offs)/ Recoveries	58	1,993	72	741
(Payments)/ Disbursements	(369)	(3,950)	(2,019)	(4,269)
(Removals)/ Additions	0	5,907	0	5,907
Ending Balance	15,659	16,656	15,659	16,656
BBCC
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	97	147	112	578
(Charge-offs)/ Recoveries	2	(52)	8	(22)
(Payments)/ Disbursements	(10)	43	(31)	(418)
(Removals)/ Additions	0	0	0	0
Ending Balance	89	138	89	138
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	2,582	3,012	2,824	3,107
(Charge-offs)/ Recoveries	(7)	0	(11)	0
(Payments)/ Disbursements	(108)	(171)	(346)	(266)
(Removals)/ Additions	0	0	0	0
Ending Balance	2,467	2,841	2,467	2,841
Indirect
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	0	0	0	0
(Charge-offs)/ Recoveries	1	2	4	7
(Payments)/ Disbursements	(1)	(2)	(4)	(7)
(Removals)/ Additions	0	0	0	0
Ending Balance	0	0	0	0
Direct
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	665	779	739	983
(Charge-offs)/ Recoveries	0	(11)	3	(9)
(Payments)/ Disbursements	(15)	(18)	(92)	(224)
(Removals)/ Additions	0	0	0	0
Ending Balance	650	750	650	750
Home equity
Financing Receivable, Troubled Debt Restructuring [Roll Forward]
Beginning Balance	217	367	282	381
(Charge-offs)/ Recoveries	1	1	2	2
(Payments)/ Disbursements	(10)	(77)	(76)	(92)
(Removals)/ Additions	0	0	0	0
Ending Balance	$ 208	$ 291	$ 208	$ 291

Amount of new troubled debt restructurings during the period.

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- Definition

Financing receivables impaired troubled debt restructuring payments disbursements.

+ References

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- Definition

Financing Receivable, Troubled Debt Restructuring

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Financing receivables impaired troubled debt restructuring write down recoveries.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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