Securities - Summary of held to maturity securities in unrealized loss position (Details 3) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Summary of held to maturity securities in an unrealized loss position
Fair Value, Less than 12 Months	$ 5,089
Unrealized Loss, Less than 12 Months	242
Fair Value, 12 Months or More
Unrealized Loss, 12 Months or More
Fair Value, Total	5,089
Unrealized Loss, Total	242
State and political subdivisions
Summary of held to maturity securities in an unrealized loss position
Fair Value, Less than 12 Months	374
Unrealized Loss, Less than 12 Months	4
Fair Value, 12 Months or More
Unrealized Loss, 12 Months or More
Fair Value, Total	374
Unrealized Loss, Total	4
Mortgage-backed securities
Summary of held to maturity securities in an unrealized loss position
Fair Value, Less than 12 Months	4,715
Unrealized Loss, Less than 12 Months	238
Fair Value, 12 Months or More
Unrealized Loss, 12 Months or More
Fair Value, Total	4,715
Unrealized Loss, Total	$ 238