Earnings per Share (Details) (USD $) In Thousands, except Share data, 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
Net income (loss) available to common stockholders	$ (5,696)	$ (6,161)	$ (715)	$ (2,676)	$ (6)	$ 747	$ 505	$ 396	$ (15,248)	$ 1,642	$ 1,451
Weighted-average shares outstanding during the period:
Basic									6,610,896	6,702,503	6,812,365
Diluted									6,610,896	6,702,503	6,812,365
Net income (loss) per common share:
Basic and diluted earnings per share (in dollors per share)	$ (0.86)	$ (0.93)	$ (0.11)	$ (0.41)	$ (0.01)	$ 0.12	$ 0.07	$ 0.06	$ (2.31)	$ 0.24	$ 0.21