Fair Value of Financial Instruments Fair Value by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	$ 100,272	$ 72,838	$ 64,803	$ 57,355
Available-for-Sale	305,589	300,200	347,159
Held-to-Maturity at Amortized Cost	330,124	335,907	335,211
Held-To-Maturity Securities, at Fair Value	324,938	335,901	335,105
Equity Securities	1,579	0	0
Federal Home Loan Bank and Federal Reserve Bank Stock	4,780	9,949	6,826
Net Loans	1,973,980	1,932,184	1,793,589
Deposits	2,411,273	2,245,116	2,256,536
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase	74,957	64,966	32,035
Federal Home Loan Bank Overnight Advances	0	105,000	32,000
Federal Home Loan Bank Term Advances	45,000	55,000	55,000
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts	20,000	20,000	20,000
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	100,272		64,803
Net Loans	1,973,980	1,932,184	1,793,589
Accrued Interest Receivable	7,662	6,753	7,530
Deposits	2,411,273	2,245,116	2,256,536
Accrued Interest Payable	361	410	240
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	100,272	72,838	64,803
Available-for-Sale	305,589	300,200	347,159
Held-To-Maturity Securities, at Fair Value	324,938	335,901	335,105
Equity Securities	1,579
Federal Home Loan Bank and Federal Reserve Bank Stock, Fair Value Disclosure	4,780	9,949	6,826
Net Loans, Fair Value Disclosure	1,915,978	1,901,046	1,773,895
Accrued Interest Receivable, Fair Value Disclosure	7,662	6,753	7,530
Deposits, Fair Value Disclosure	2,402,122	2,236,548	2,248,066
Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Fair Value Disclosure	74,957	64,966	32,035
Federal Funds Purchased, Fair Value Disclosure		105,000	32,000
Federal Home Loan Bank Term Advances, Fair Value Disclosure	44,484	54,781	55,130
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts, Fair Value Disclosure	20,000	20,000	20,000
Accrued Interest Payable, Fair Value Disclosure	361	410	240
Quoted Prices In Active Markets for Indentical Assets (Level 1) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	100,272	72,838	64,803
Available-for-Sale	0	59,894	54,695
Held-To-Maturity Securities, at Fair Value	0	0	0
Equity Securities	0
Federal Home Loan Bank and Federal Reserve Bank Stock, Fair Value Disclosure	0	0	0
Net Loans, Fair Value Disclosure	0	0	0
Accrued Interest Receivable, Fair Value Disclosure	0	0	0
Deposits, Fair Value Disclosure	0	0	0
Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Fair Value Disclosure	0	0	0
Federal Funds Purchased, Fair Value Disclosure		0	0
Federal Home Loan Bank Term Advances, Fair Value Disclosure	0	0	0
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts, Fair Value Disclosure	0	0	0
Accrued Interest Payable, Fair Value Disclosure	0	0	0
Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0	0
Available-for-Sale	305,589	240,306	292,464
Held-To-Maturity Securities, at Fair Value	324,938	335,901	335,105
Equity Securities	1,579
Federal Home Loan Bank and Federal Reserve Bank Stock, Fair Value Disclosure	4,780	9,949	6,826
Net Loans, Fair Value Disclosure	0	0	0
Accrued Interest Receivable, Fair Value Disclosure	7,662	6,753	7,530
Deposits, Fair Value Disclosure	2,402,122	2,236,548	2,248,066
Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Fair Value Disclosure	74,957	64,966	32,035
Federal Funds Purchased, Fair Value Disclosure		105,000	32,000
Federal Home Loan Bank Term Advances, Fair Value Disclosure	44,484	54,781	55,130
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts, Fair Value Disclosure	20,000	20,000	20,000
Accrued Interest Payable, Fair Value Disclosure	361	410	240
Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0	0
Available-for-Sale	0	0	0
Held-To-Maturity Securities, at Fair Value	0	0	0
Equity Securities	0
Federal Home Loan Bank and Federal Reserve Bank Stock, Fair Value Disclosure	0	0	0
Net Loans, Fair Value Disclosure	1,915,978	1,901,046	1,773,895
Accrued Interest Receivable, Fair Value Disclosure	0	0	0
Deposits, Fair Value Disclosure	0	0	0
Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Fair Value Disclosure	0	0	0
Federal Funds Purchased, Fair Value Disclosure		0	0
Federal Home Loan Bank Term Advances, Fair Value Disclosure	0	0	0
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts, Fair Value Disclosure	0	0	0
Accrued Interest Payable, Fair Value Disclosure	$ 0	$ 0	$ 0