Allowance for Credit Losses - Credit Quality Indicators by Commercial and Industrial Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases, net of unearned income and deferred costs and fees	$ 5,096,778	$ 5,260,327
Commercial and industrial | Commercial real estate other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	99,293	93,073
One year before current fiscal year	63,221	73,311
Two years before current fiscal year	57,956	57,468
Three years before current fiscal year	47,136	62,111
Four years before current fiscal year	44,442	35,739
Prior	265,859	302,038
Revolving Loans Amortized Cost Basis	140,324	152,946
Revolving Loans Converted to Term	9,713	16,301
Total loans and leases, net of unearned income and deferred costs and fees	727,944	792,987
Commercial and industrial | Commercial real estate other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	99,129	91,597
One year before current fiscal year	62,023	72,639
Two years before current fiscal year	57,126	56,191
Three years before current fiscal year	46,264	60,714
Four years before current fiscal year	43,901	33,402
Prior	264,656	301,027
Revolving Loans Amortized Cost Basis	138,153	149,969
Revolving Loans Converted to Term	9,713	16,301
Total loans and leases, net of unearned income and deferred costs and fees	720,965	781,840
Commercial and industrial | Commercial real estate other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	164	1,064
One year before current fiscal year	815	367
Two years before current fiscal year	532	344
Three years before current fiscal year	141	912
Four years before current fiscal year	310	2,045
Prior	523	228
Revolving Loans Amortized Cost Basis	705	1,331
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	3,190	6,291
Commercial and industrial | Commercial real estate other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	412
One year before current fiscal year	383	305
Two years before current fiscal year	298	933
Three years before current fiscal year	731	485
Four years before current fiscal year	231	292
Prior	680	783
Revolving Loans Amortized Cost Basis	1,466	1,646
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	3,789	4,856
Commercial and industrial | PPP loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	139,564	291,252
One year before current fiscal year	2,366	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	141,930	291,252
Commercial and industrial | PPP loans | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	139,564	291,252
One year before current fiscal year	2,366	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	141,930	291,252
Commercial and industrial | PPP loans | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	0	0
Commercial and industrial | PPP loans | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	0	0
Commercial and industrial | Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	4,615	11,635
One year before current fiscal year	7,825	8,088
Two years before current fiscal year	6,052	11,190
Three years before current fiscal year	9,521	7,462
Four years before current fiscal year	6,345	3,539
Prior	5,918	4,907
Revolving Loans Amortized Cost Basis	37,493	46,328
Revolving Loans Converted to Term	566	1,340
Total loans and leases, net of unearned income and deferred costs and fees	78,335	94,489
Commercial and industrial | Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	4,615	11,536
One year before current fiscal year	7,736	8,005
Two years before current fiscal year	6,035	11,162
Three years before current fiscal year	9,497	6,531
Four years before current fiscal year	6,239	3,539
Prior	3,590	2,599
Revolving Loans Amortized Cost Basis	35,276	41,936
Revolving Loans Converted to Term	566	1,340
Total loans and leases, net of unearned income and deferred costs and fees	73,554	86,648
Commercial and industrial | Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	28
Three years before current fiscal year	24	729
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	225	2,080
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	249	2,837
Commercial and industrial | Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	99
One year before current fiscal year	89	83
Two years before current fiscal year	17	0
Three years before current fiscal year	0	202
Four years before current fiscal year	106	0
Prior	2,328	2,308
Revolving Loans Amortized Cost Basis	1,992	2,312
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	4,532	5,004
Commercial real estate | Commercial real estate other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	229,984	278,782
One year before current fiscal year	271,526	264,280
Two years before current fiscal year	272,290	256,658
Three years before current fiscal year	226,716	248,313
Four years before current fiscal year	237,536	330,041
Prior	925,221	727,711
Revolving Loans Amortized Cost Basis	56,551	33,622
Revolving Loans Converted to Term	33,366	64,903
Total loans and leases, net of unearned income and deferred costs and fees	2,253,190	2,204,310
Commercial real estate | Commercial real estate other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	229,984	278,747
One year before current fiscal year	269,752	246,331
Two years before current fiscal year	255,296	232,651
Three years before current fiscal year	205,093	237,487
Four years before current fiscal year	226,830	290,106
Prior	824,671	664,027
Revolving Loans Amortized Cost Basis	56,018	33,117
Revolving Loans Converted to Term	33,366	64,903
Total loans and leases, net of unearned income and deferred costs and fees	2,101,010	2,047,369
Commercial real estate | Commercial real estate other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	35
One year before current fiscal year	1,774	13,016
Two years before current fiscal year	11,982	5,612
Three years before current fiscal year	3,151	4,654
Four years before current fiscal year	2,190	34,310
Prior	74,499	46,074
Revolving Loans Amortized Cost Basis	360	203
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	93,956	103,904
Commercial real estate | Commercial real estate other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	4,933
Two years before current fiscal year	5,012	18,395
Three years before current fiscal year	18,472	6,172
Four years before current fiscal year	8,516	5,625
Prior	26,051	17,610
Revolving Loans Amortized Cost Basis	173	302
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	58,224	53,037
Commercial real estate | Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	13,096	24,400
One year before current fiscal year	22,546	35,081
Two years before current fiscal year	30,564	45,094
Three years before current fiscal year	42,375	25,499
Four years before current fiscal year	23,616	18,847
Prior	55,132	46,092
Revolving Loans Amortized Cost Basis	2,301	1,251
Revolving Loans Converted to Term	2,553	5,602
Total loans and leases, net of unearned income and deferred costs and fees	192,183	201,866
Commercial real estate | Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	13,096	22,440
One year before current fiscal year	22,063	35,081
Two years before current fiscal year	30,564	44,519
Three years before current fiscal year	42,335	22,356
Four years before current fiscal year	23,616	17,081
Prior	53,458	44,559
Revolving Loans Amortized Cost Basis	2,252	919
Revolving Loans Converted to Term	2,553	5,602
Total loans and leases, net of unearned income and deferred costs and fees	189,937	192,557
Commercial real estate | Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	1,960
One year before current fiscal year	483	0
Two years before current fiscal year	0	575
Three years before current fiscal year	0	1,366
Four years before current fiscal year	0	1,053
Prior	381	6
Revolving Loans Amortized Cost Basis	49	49
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	913	5,009
Commercial real estate | Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	40	1,777
Four years before current fiscal year	0	713
Prior	1,293	1,527
Revolving Loans Amortized Cost Basis	0	283
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	1,333	4,300
Commercial real estate | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	10,828	14,465
One year before current fiscal year	11,619	20,705
Two years before current fiscal year	17,533	7,999
Three years before current fiscal year	7,591	2,478
Four years before current fiscal year	1,343	1,879
Prior	8,039	7,473
Revolving Loans Amortized Cost Basis	106,545	86,966
Revolving Loans Converted to Term	7,148	21,051
Total loans and leases, net of unearned income and deferred costs and fees	170,646	163,016
Commercial real estate | Construction | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	10,828	14,465
One year before current fiscal year	11,619	20,705
Two years before current fiscal year	17,533	7,999
Three years before current fiscal year	7,591	2,478
Four years before current fiscal year	1,343	1,879
Prior	7,391	6,682
Revolving Loans Amortized Cost Basis	105,778	85,513
Revolving Loans Converted to Term	7,148	21,051
Total loans and leases, net of unearned income and deferred costs and fees	169,231	160,772
Commercial real estate | Construction | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	467
Revolving Loans Amortized Cost Basis	0	1,453
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	0	1,920
Commercial real estate | Construction | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current fiscal year	0	0
One year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	648	324
Revolving Loans Amortized Cost Basis	767	0
Revolving Loans Converted to Term	0	0
Total loans and leases, net of unearned income and deferred costs and fees	$ 1,415	$ 324