Income Taxes - Provision for Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Federal current expense									$ 1,562	$ 1,199	$ 757
Federal deferred income tax expense (benefit)									372	(43)	469
Total Income Tax expense	$ 491	$ 538	$ 324	$ 581	$ 329	$ 500	$ 61	$ 266	$ 1,934	$ 1,156	$ 1,226