Fair Value of Financial Instruments Fair Value - Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	$ 315,459	$ 346,996	$ 339,190
Available-for-sale Securities, Amortized Cost Basis	315,329	347,615	334,291
With a Related Allowance		0	2,640
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	315,459	346,996	339,190
Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	64,730	54,706	0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	250,729	292,290	339,190
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans	1,502	0	2,640
Gain (Loss) on Collateral Dependent Impaired Loans	(138)	0	(240)
Other Real Estate and Repossessed Assets, Net	1,713	1,686	1,016
Gain (Loss) Other Real Estate and Repossessed Assets, Net	(655)	(587)	(319)
Fair Value, Measurements, Nonrecurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans	0	0	0
Other Real Estate and Repossessed Assets, Net	0	0	0
Fair Value, Measurements, Nonrecurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans	0	0	0
Other Real Estate and Repossessed Assets, Net	0	0	0
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans	1,502	0	2,640
Other Real Estate and Repossessed Assets, Net	1,713	1,686	1,016
U.S. Agency Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	146,978	147,377	153,926
Available-for-sale Securities, Amortized Cost Basis	146,976	147,110	152,511
U.S. Agency Obligations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	146,978	147,377	153,926
U.S. Agency Obligations | Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	64,730	54,706	0
U.S. Agency Obligations | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	82,248	92,671	153,926
U.S. Agency Obligations | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
State and Municipal Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	11,902	27,690	31,628
Available-for-sale Securities, Amortized Cost Basis	11,875	27,684	31,562
State and Municipal Obligations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	11,902	27,690	31,628
State and Municipal Obligations | Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
State and Municipal Obligations | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	11,902	27,690	31,628
State and Municipal Obligations | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mortgage-Backed Securities - Residential | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	152,806	167,239	148,087
Mortgage-Backed Securities - Residential | Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mortgage-Backed Securities - Residential | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	152,806	167,239	148,087
Mortgage-Backed Securities - Residential | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Corporate and Other Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	2,299	3,308	4,299
Available-for-sale Securities, Amortized Cost Basis	2,500	3,512	4,500
Corporate and Other Debt Securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	2,299	3,308	4,299
Corporate and Other Debt Securities | Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Corporate and Other Debt Securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	2,299	3,308	4,299
Corporate and Other Debt Securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mutual Funds and Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,474	1,382	1,250
Available-for-sale Securities, Amortized Cost Basis	1,120	1,120	1,120
Mutual Funds and Equity Securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,474	1,382	1,250
Available-for-sale Securities, Amortized Cost Basis	1,500
Mutual Funds and Equity Securities | Fair Value, Measurements, Recurring | Quoted Prices In Active Markets for Indentical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mutual Funds and Equity Securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,474	1,382	1,250
Mutual Funds and Equity Securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	$ 0	$ 0	$ 0