| Fair Value (Details 4) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 | Dec. 31, 2012 | 
|---|---|---|
| Impaired loans | $ 17,253 | $ 17,879 | 
| Foreclosed real estate | 447 | 425 | 
| Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member] | ||
| Impaired loans | 0 | 0 | 
| Foreclosed real estate | 0 | 0 | 
| Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member] | ||
| Impaired loans | 0 | 0 | 
| Foreclosed real estate | 0 | 0 | 
| Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | ||
| Impaired loans | 17,253 | 17,879 | 
| Foreclosed real estate | $ 447 | $ 425 |