Loans and Leases - Schedule of Past Due Loans and Leases (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Financing Receivable, Past Due [Line Items]    
Total $ 4,859,517 $ 4,837,735
Less: unearned income and deferred costs and fees (3,715) (3,796)
Total loans and leases, net of unearned income and deferred costs and fees 4,855,802 4,833,939
Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 4,601,650 4,556,048
Total 4,612,198 4,572,537
90 days and accruing 0 0
Nonaccrual 16,543 19,340
Less: unearned income and deferred costs and fees (3,715) (3,796)
Less: unearned income and deferred costs and fees, Current Loans (3,715) (3,796)
Less: unearned income and deferred costs and fees, 90 days and accruing 0 0
Less: unearned income and deferred costs and fees, Nonaccrual 0 0
Total loans and leases, net of unearned income and deferred costs and fees 4,608,483 4,568,741
Total originated loans and leases, net of unearned income and deferred costs and fees, current loans 4,597,935 4,552,252
Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 3,883 7,838
Less: unearned income and deferred costs and fees 0 0
Total loans and leases, net of unearned income and deferred costs and fees 3,883 7,838
Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 6,665 8,651
Less: unearned income and deferred costs and fees 0 0
Total loans and leases, net of unearned income and deferred costs and fees 6,665 8,651
Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Current Loans 244,695 262,510
Total 247,319 265,198
90 days and accruing 1,229 1,316
Nonaccrual 2,363 2,856
Less: unearned income and deferred costs and fees 0 0
Total loans and leases, net of unearned income and deferred costs and fees 247,319 265,198
Total Acquired Loans | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 493 67
Total Acquired Loans | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 2,131 2,621
Commercial and industrial    
Financing Receivable, Past Due [Line Items]    
Total 1,043,789 1,077,635
Commercial and industrial | Agriculture    
Financing Receivable, Past Due [Line Items]    
Total 93,406 107,494
Commercial and industrial | Other    
Financing Receivable, Past Due [Line Items]    
Total 950,383 970,141
Commercial and industrial | Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 999,741 1,029,897
Total 1,002,351 1,033,923
90 days and accruing 0 0
Nonaccrual 1,867 1,861
Commercial and industrial | Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 170 2,367
Commercial and industrial | Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 2,440 1,659
Commercial and industrial | Originated Loans and Leases | Agriculture    
Financing Receivable, Past Due [Line Items]    
Current Loans 93,406 107,494
Total 93,406 107,494
90 days and accruing 0 0
Nonaccrual 0 0
Commercial and industrial | Originated Loans and Leases | Agriculture | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial and industrial | Originated Loans and Leases | Agriculture | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial and industrial | Originated Loans and Leases | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 906,335 922,403
Total 908,945 926,429
90 days and accruing 0 0
Nonaccrual 1,867 1,861
Commercial and industrial | Originated Loans and Leases | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 170 2,367
Commercial and industrial | Originated Loans and Leases | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 2,440 1,659
Commercial and industrial | Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Current Loans 41,433 43,702
Total 41,438 43,712
90 days and accruing 5 10
Nonaccrual 7 22
Commercial and industrial | Total Acquired Loans | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial and industrial | Total Acquired Loans | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 5 10
Commercial and industrial | Total Acquired Loans | Agriculture    
Financing Receivable, Past Due [Line Items]    
Total 0 0
Commercial and industrial | Total Acquired Loans | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 41,433 43,702
Total 41,438 43,712
90 days and accruing 5 10
Nonaccrual 7 22
Commercial and industrial | Total Acquired Loans | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial and industrial | Total Acquired Loans | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 5 10
Commercial real estate    
Financing Receivable, Past Due [Line Items]    
Total 2,401,976 2,340,661
Commercial real estate | Agriculture    
Financing Receivable, Past Due [Line Items]    
Total 180,698 170,229
Commercial real estate | Other    
Financing Receivable, Past Due [Line Items]    
Total 2,034,240 2,004,763
Commercial real estate | Construction    
Financing Receivable, Past Due [Line Items]    
Total 187,038 165,669
Commercial real estate | Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 2,232,997 2,158,441
Total 2,235,213 2,161,569
90 days and accruing 0 0
Nonaccrual 5,230 7,691
Commercial real estate | Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 775 1,272
Commercial real estate | Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 1,441 1,856
Commercial real estate | Originated Loans and Leases | Agriculture    
Financing Receivable, Past Due [Line Items]    
Current Loans 180,330 169,934
Total 180,479 170,005
90 days and accruing 0 0
Nonaccrual 0 0
Commercial real estate | Originated Loans and Leases | Agriculture | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 149 71
Commercial real estate | Originated Loans and Leases | Agriculture | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Originated Loans and Leases | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 1,867,200 1,824,222
Total 1,869,057 1,827,279
90 days and accruing 0 0
Nonaccrual 5,230 7,691
Commercial real estate | Originated Loans and Leases | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 416 1,201
Commercial real estate | Originated Loans and Leases | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 1,441 1,856
Commercial real estate | Originated Loans and Leases | Construction    
Financing Receivable, Past Due [Line Items]    
Current Loans 185,467 164,285
Total 185,677 164,285
90 days and accruing 0 0
Nonaccrual 0 0
Commercial real estate | Originated Loans and Leases | Construction | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 210 0
Commercial real estate | Originated Loans and Leases | Construction | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Current Loans 165,928 178,253
Total 166,763 179,092
90 days and accruing 551 525
Nonaccrual 309 316
Commercial real estate | Total Acquired Loans | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 835 839
Commercial real estate | Total Acquired Loans | Agriculture    
Financing Receivable, Past Due [Line Items]    
Current Loans 219 224
Total 219 224
90 days and accruing 0 0
Nonaccrual 0 0
Commercial real estate | Total Acquired Loans | Agriculture | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans | Agriculture | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 164,348 176,645
Total 165,183 177,484
90 days and accruing 551 525
Nonaccrual 309 316
Commercial real estate | Total Acquired Loans | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 835 839
Commercial real estate | Total Acquired Loans | Construction    
Financing Receivable, Past Due [Line Items]    
Current Loans 1,361 1,384
Total 1,361 1,384
90 days and accruing 0 0
Nonaccrual 0 0
Commercial real estate | Total Acquired Loans | Construction | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Commercial real estate | Total Acquired Loans | Construction | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Residential real estate    
Financing Receivable, Past Due [Line Items]    
Total 1,324,206 1,333,894
Residential real estate | Home equity    
Financing Receivable, Past Due [Line Items]    
Total 222,713 229,608
Residential real estate | Mortgages    
Financing Receivable, Past Due [Line Items]    
Total 1,101,493 1,104,286
Residential real estate | Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 1,280,739 1,283,529
Total 1,285,893 1,292,261
90 days and accruing 0 0
Nonaccrual 9,267 9,554
Residential real estate | Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 2,410 3,679
Residential real estate | Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 2,744 5,053
Residential real estate | Originated Loans and Leases | Home equity    
Financing Receivable, Past Due [Line Items]    
Current Loans 202,439 206,447
Total 204,058 208,459
90 days and accruing 0 0
Nonaccrual 1,984 1,784
Residential real estate | Originated Loans and Leases | Home equity | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 927 986
Residential real estate | Originated Loans and Leases | Home equity | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 692 1,026
Residential real estate | Originated Loans and Leases | Mortgages    
Financing Receivable, Past Due [Line Items]    
Current Loans 1,078,300 1,077,082
Total 1,081,835 1,083,802
90 days and accruing 0 0
Nonaccrual 7,283 7,770
Residential real estate | Originated Loans and Leases | Mortgages | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 1,483 2,693
Residential real estate | Originated Loans and Leases | Mortgages | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 2,052 4,027
Residential real estate | Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Current Loans 36,529 39,797
Total 38,313 41,633
90 days and accruing 673 781
Nonaccrual 2,047 2,518
Residential real estate | Total Acquired Loans | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 493 64
Residential real estate | Total Acquired Loans | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 1,291 1,772
Residential real estate | Total Acquired Loans | Home equity    
Financing Receivable, Past Due [Line Items]    
Current Loans 17,902 20,300
Total 18,655 21,149
90 days and accruing 59 59
Nonaccrual 1,053 1,414
Residential real estate | Total Acquired Loans | Home equity | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 492 46
Residential real estate | Total Acquired Loans | Home equity | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 261 803
Residential real estate | Total Acquired Loans | Mortgages    
Financing Receivable, Past Due [Line Items]    
Current Loans 18,627 19,497
Total 19,658 20,484
90 days and accruing 614 722
Nonaccrual 994 1,104
Residential real estate | Total Acquired Loans | Mortgages | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 1 18
Residential real estate | Total Acquired Loans | Mortgages | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 1,030 969
Consumer and other    
Financing Receivable, Past Due [Line Items]    
Total 73,689 70,989
Consumer and other | Other    
Financing Receivable, Past Due [Line Items]    
Total 59,686 58,326
Consumer and other | Indirect    
Financing Receivable, Past Due [Line Items]    
Total 14,003 12,663
Consumer and other | Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 72,316 69,625
Total 72,884 70,228
90 days and accruing 0 0
Nonaccrual 179 234
Consumer and other | Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 528 520
Consumer and other | Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 40 83
Consumer and other | Originated Loans and Leases | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 58,658 57,354
Total 58,881 57,565
90 days and accruing 0 0
Nonaccrual 74 79
Consumer and other | Originated Loans and Leases | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 205 187
Consumer and other | Originated Loans and Leases | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 18 24
Consumer and other | Originated Loans and Leases | Indirect    
Financing Receivable, Past Due [Line Items]    
Current Loans 13,658 12,271
Total 14,003 12,663
90 days and accruing 0 0
Nonaccrual 105 155
Consumer and other | Originated Loans and Leases | Indirect | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 323 333
Consumer and other | Originated Loans and Leases | Indirect | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 22 59
Consumer and other | Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Current Loans 805 758
Total 805 761
90 days and accruing 0 0
Nonaccrual 0 0
Consumer and other | Total Acquired Loans | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 3
Consumer and other | Total Acquired Loans | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Consumer and other | Total Acquired Loans | Other    
Financing Receivable, Past Due [Line Items]    
Current Loans 805 758
Total 805 761
90 days and accruing 0 0
Nonaccrual 0 0
Consumer and other | Total Acquired Loans | Other | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 3
Consumer and other | Total Acquired Loans | Other | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Consumer and other | Total Acquired Loans | Indirect    
Financing Receivable, Past Due [Line Items]    
Total 0 0
Leases    
Financing Receivable, Past Due [Line Items]    
Total 15,857 14,556
Leases | Originated Loans and Leases    
Financing Receivable, Past Due [Line Items]    
Current Loans 15,857 14,556
Total 15,857 14,556
90 days and accruing 0 0
Nonaccrual 0 0
Leases | Originated Loans and Leases | 30-89 days    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Leases | Originated Loans and Leases | 90 days or more    
Financing Receivable, Past Due [Line Items]    
Past due 0 0
Leases | Total Acquired Loans    
Financing Receivable, Past Due [Line Items]    
Total $ 0 $ 0