Disclosures About Fair Value of Assets and Liabilities - Measurement of fair value of assets on recurring basis (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Available-for-sale Securities:
Total Available-for-sale securities	$ 50,337	$ 28,004
Recurring | Fair Value
Available-for-sale Securities:
Total Available-for-sale securities	50,337	28,004
Recurring | Fair Value | U.S. government-sponsored agencies
Available-for-sale Securities:
Total Available-for-sale securities	23,218	10,709
Recurring | Fair Value | Mortgage-backed securities
Available-for-sale Securities:
Total Available-for-sale securities	10,809	7,198
Recurring | Fair Value | State and political subdivisions
Available-for-sale Securities:
Total Available-for-sale securities	16,310	10,097
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government-sponsored agencies
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | State and political subdivisions
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Significant Other Observable Inputs (Level 2)
Available-for-sale Securities:
Total Available-for-sale securities	50,337	28,004
Recurring | Significant Other Observable Inputs (Level 2) | U.S. government-sponsored agencies
Available-for-sale Securities:
Total Available-for-sale securities	23,218	10,709
Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities
Available-for-sale Securities:
Total Available-for-sale securities	10,809	7,198
Recurring | Significant Other Observable Inputs (Level 2) | State and political subdivisions
Available-for-sale Securities:
Total Available-for-sale securities	16,310	10,097
Recurring | Significant Unobservable Inputs (Level 3)
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Significant Unobservable Inputs (Level 3) | U.S. government-sponsored agencies
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities
Available-for-sale Securities:
Total Available-for-sale securities
Recurring | Significant Unobservable Inputs (Level 3) | State and political subdivisions
Available-for-sale Securities:
Total Available-for-sale securities