Earnings (Loss) Per Share (Details) (USD $)	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, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Basic
Net income (loss) attributable to common shares	$ 3,049,000	$ 2,616,000	$ 3,288,000	$ 2,552,000	$ 29,991,000	$ 2,682,000	$ 2,381,000	$ 1,088,000	$ (5,282,000)	$ (5,682,000)	$ (684,000)	$ (2,963,000)	$ 11,505,000	$ 36,142,000	$ (14,611,000)
Weighted average common shares outstanding													8,625,198	8,602,845	8,507,572
Basic earnings (loss) per common share	$ 0.35	$ 0.30	$ 0.38	$ 0.30	$ 3.49	$ 0.31	$ 0.28	$ 0.13	$ (0.62)	$ (0.67)	$ (0.08)	$ (0.35)	$ 1.33	$ 4.20	$ (1.72)
Diluted
Net income (loss) attributable to common shares													$ 11,505,000	$ 36,142,000	$ (14,611,000)
Weighted average common shares outstanding for basic earnings (loss) per common share													8,625,198	8,602,845	8,507,572
Weighted average common shares outstanding for basic earnings (loss) per common share													8,625,198	8,602,845	8,507,572
Add: Dilutive effects of share-based awards													224,429	275,335	0
Average shares and dilutive potential common shares													8,849,627	8,878,180	8,507,572
Diluted earnings (loss) per common share	$ 0.35	$ 0.30	$ 0.36	$ 0.28	$ 3.37	$ 0.30	$ 0.27	$ 0.12	$ (0.62)	$ (0.67)	$ (0.08)	$ (0.35)	$ 1.30	$ 4.07	$ (1.72)