Fair Value of Financial Instruments Fair Value - Recurring and Nonrecurring (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	$ 501,574	$ 478,698	$ 431,010
Other Real Estate and Repossessed Assets, Net	1,175	1,034	837
Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	501,574	478,698	431,010
Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	249
Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	501,574	478,698	430,761
Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Impaired Loans	0	1,020	486
Other Real Estate and Repossessed Assets, Net	1,175	1,034	837
Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Impaired Loans	0	0	0
Other Real Estate and Repossessed Assets, Net	0	0	0
Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Impaired Loans	0	0	0
Other Real Estate and Repossessed Assets, Net	0	0	0
Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Impaired Loans	0	1,020	486
Other Real Estate and Repossessed Assets, Net	1,175	1,034	837
U.S. Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	150,046	122,457	48,655
U.S. Agency Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	150,046	122,457	48,655
U.S. Agency Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
U.S. Agency Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	150,046	122,457	48,655
U.S. Agency Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
State and Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	130,444	84,838	55,013
State and Municipal Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	130,444	84,838	55,013
State and Municipal Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
State and Municipal Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	130,444	84,838	55,013
State and Municipal Obligations [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mortgage-Backed Securities - Residential [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	203,230	261,804	325,076
Mortgage-Backed Securities - Residential [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mortgage-Backed Securities - Residential [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	203,230	261,804	325,076
Mortgage-Backed Securities - Residential [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Corporate and Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	16,711	8,451	801
Corporate and Other Debt Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	16,711	8,451	801
Corporate and Other Debt Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Corporate and Other Debt Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	16,711	8,451	801
Corporate and Other Debt Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	0
Mutual Funds and Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,143	1,148	1,465
Mutual Funds and Equity Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,143	1,148	1,465
Mutual Funds and Equity Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Quoted Prices In Active Markets for Indentical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	0	0	249
Mutual Funds and Equity Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	1,143	1,148	1,216
Mutual Funds and Equity Securities [Member] | Fair Value of Assets and Liabilities Measured on a Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-Sale	$ 0	$ 0	$ 0