Allowance for Loan and Lease Losses (Details 6) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Originated Loans and Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	$ 2,786,570	$ 2,635,335
Originated Loans and Leases | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	2,728,550	2,594,534
Originated Loans and Leases | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	38,488	20,485
Originated Loans and Leases | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	19,532	20,316
Originated Loans and Leases | Commercial and industrial other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	977,891	847,055
Originated Loans and Leases | Commercial and industrial other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	965,156	836,788
Originated Loans and Leases | Commercial and industrial other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	7,545	7,218
Originated Loans and Leases | Commercial and industrial other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	5,190	3,049
Originated Loans and Leases | Commercial and industrial - Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	89,017	118,247
Originated Loans and Leases | Commercial and industrial - Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	78,390	117,135
Originated Loans and Leases | Commercial and industrial - Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	10,570	755
Originated Loans and Leases | Commercial and industrial - Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	57	357
Originated Loans and Leases | Commercial real estate other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	1,503,385	1,431,690
Originated Loans and Leases | Commercial real estate other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	1,477,335	1,403,370
Originated Loans and Leases | Commercial real estate other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	11,765	11,939
Originated Loans and Leases | Commercial real estate other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	14,285	16,381
Originated Loans and Leases | Commercial real estate - Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	120,643	102,509
Originated Loans and Leases | Commercial real estate - Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	112,035	101,407
Originated Loans and Leases | Commercial real estate - Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	8,608	573
Originated Loans and Leases | Commercial real estate - Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	529
Originated Loans and Leases | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	95,634	135,834
Originated Loans and Leases | Commercial real estate - Construction | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	95,634	135,834
Originated Loans and Leases | Commercial real estate - Construction | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Originated Loans and Leases | Commercial real estate - Construction | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	289,689	330,125
Total Acquired Loans | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	280,346	316,458
Total Acquired Loans | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	547	526
Total Acquired Loans | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	8,796	13,141
Total Acquired Loans | Commercial and industrial other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	61,134	79,317
Total Acquired Loans | Commercial and industrial other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	60,019	77,921
Total Acquired Loans | Commercial and industrial other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial and industrial other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	1,115	1,396
Total Acquired Loans | Commercial and industrial - Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial and industrial - Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial and industrial - Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial and industrial - Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial real estate other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	226,772	241,605
Total Acquired Loans | Commercial real estate other | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	218,544	229,334
Total Acquired Loans | Commercial real estate other | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	547	526
Total Acquired Loans | Commercial real estate other | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	7,681	11,745
Total Acquired Loans | Commercial real estate - Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	257	267
Total Acquired Loans | Commercial real estate - Agriculture | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	257	267
Total Acquired Loans | Commercial real estate - Agriculture | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial real estate - Agriculture | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	1,526	8,936
Total Acquired Loans | Commercial real estate - Construction | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	1,526	8,936
Total Acquired Loans | Commercial real estate - Construction | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	0	0
Total Acquired Loans | Commercial real estate - Construction | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases, gross	$ 0	$ 0