Loans and Allowance for Credit Losses - Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	$ 14,463	$ 11,120
Nonaccrual With No ACL	8,352	10,723
Government guarantees
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	1,382	1,483
Nonaccrual With No ACL	1,350	1,483
Net of government guarantees
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	13,081	9,637
Nonaccrual With No ACL	7,002	9,240
Commercial & industrial loans
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	6,212	3,848
Nonaccrual With No ACL	2,300	3,513
Commercial real estate | Owner occupied properties
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	4,056	4,620
Nonaccrual With No ACL	4,016	4,582
Residential | 1-4 family residential properties secured by first liens
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	2,292	160
Nonaccrual With No ACL	154	160
Residential | 1-4 family residential properties secured by junior liens and revolving secured by 1-4 family first liens
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	239	242
Nonaccrual With No ACL	220	221
Residential | 1-4 family residential construction loans
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	117	702
Nonaccrual With No ACL	117	702
Other construction, land development and raw land loans
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	1,545	1,545
Nonaccrual With No ACL	1,545	1,545
Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	2	3
Nonaccrual With No ACL	$ 0	$ 0