Allowance for Credit Losses on Loans - Amortized Cost Basis of Collateral Dependent Loans, By Class of Loan (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 4,826,338	$ 4,307,366
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,589	2,506
Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	950	163
Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,935	1,640
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	276	620
Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	2,060
Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,056	1,242
SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	7,322	5,341
SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,214	3,848
Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	229	27
A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,946	1,952
Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	50	1,026
Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	21,567	20,425
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,936,422	2,818,782
Commercial real estate | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,589	2,506
Commercial real estate | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	950	163
Commercial real estate | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,935	1,640
Commercial real estate | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	510
Commercial real estate | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	2,060
Commercial real estate | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,056	1,242
Commercial real estate | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial real estate | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial real estate | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial real estate | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial real estate | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	1,000
Commercial real estate | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,530	9,121
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	926,835	955,050
Consumer | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8	3
Consumer | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	7,322	5,341
Consumer | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,214	3,848
Consumer | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	229	27
Consumer | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Consumer | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	10,773	9,219
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	633,897	249,791
Commercial and industrial | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	107
Commercial and industrial | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Commercial and industrial | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,933	1,926
Commercial and industrial | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	45	14
Commercial and industrial | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,978	2,047
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	284,933	249,827
Construction | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Construction | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	40,613	32,633
Agriculture production | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	268	0
Agriculture production | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Agriculture production | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	13	26
Agriculture production | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	5	12
Agriculture production | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	286	38
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,638	1,283
Leases | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
Leases | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Leases | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
Leases | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,600,284	1,609,556
CRE non-owner occupied | Commercial real estate | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,696	2,145
CRE non-owner occupied | Commercial real estate | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	1,220
CRE non-owner occupied | Commercial real estate | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	497
CRE non-owner occupied | Commercial real estate | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
CRE non-owner occupied | Commercial real estate | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE non-owner occupied | Commercial real estate | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,696	3,862
CRE owner occupied | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	581,090	546,434
CRE owner occupied | Commercial real estate | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	893	361
CRE owner occupied | Commercial real estate | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	950	163
CRE owner occupied | Commercial real estate | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,935	420
CRE owner occupied | Commercial real estate | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	13
CRE owner occupied | Commercial real estate | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE owner occupied | Commercial real estate | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE owner occupied | Commercial real estate | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE owner occupied | Commercial real estate | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
CRE owner occupied | Commercial real estate | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE owner occupied | Commercial real estate | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
CRE owner occupied | Commercial real estate | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	1,000
CRE owner occupied | Commercial real estate | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,778	1,957
Multifamily | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	602,199	517,725
Multifamily | Commercial real estate | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	2,060
Multifamily | Commercial real estate | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
Multifamily | Commercial real estate | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Multifamily | Commercial real estate | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	2,060
Farmland | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	152,849	145,067
Farmland | Commercial real estate | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,056	1,242
Farmland | Commercial real estate | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0
Farmland | Commercial real estate | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Farmland | Commercial real estate | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,056	1,242
SFR 1-4 1st DT Liens | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	511,759
SFR 1-4 1st DT Liens | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		509,508
SFR 1-4 1st DT Liens | Consumer | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	6,135	5,341
SFR 1-4 1st DT Liens | Consumer | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	190	0
SFR 1-4 1st DT Liens | Consumer | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR 1-4 1st DT Liens | Consumer | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	6,325	5,341
SFR HELOCs and junior liens | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	332,820	362,886
SFR HELOCs and junior liens | Consumer | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,187	0
SFR HELOCs and junior liens | Consumer | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,024	3,848
SFR HELOCs and junior liens | Consumer | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
SFR HELOCs and junior liens | Consumer | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,211	3,848
Other | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	82,256	82,656
Other | Consumer | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Warehouse
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8	3
Other | Consumer | Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | SFR -1st Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | SFR -2nd Deed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Automobile/Truck
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	229	27
Other | Consumer | A/R and Inventory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 237	$ 30