Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Basic EPS:
Income from continuing operations	$ 20,939	$ 84,610	$ 46,475
Income from continuing operations, share amounts	42,840,000	42,394,000	38,300,000
Less: Income (Loss) from continuing operations allocated to unvested shares	(448)	(1,598)	(879)
Income from continuing operations allocated to common shares	20,491	83,012	45,596
Income from continuing operations allocated to common shares, shares	42,840,000	42,394,000	38,300,000
Income from continuing operations allocated to common shares, per share amount	$ 0.48	$ 1.96	$ 1.19
Dilutive Securities:
Plus: Income (Loss) from continuing operations allocated to unvested shares	448	1,598	879
Less: (Income) loss from continuing operations re-allocated to unvested shares	(447)	(1,589)	(874)
Stock Options, shares	90,000	235,000	224,000
Diluted EPS:
Income loss from continuing operations allocated to common shares, and assumed share conversions	$ 20,492	$ 83,021	$ 45,601
Income from continuing operations allocated to common share, and assumed share conversions, shares	42,930,000	42,629,000	38,524,000
Income from continuing operations allocated to common shares, and assumed share conversions, per share amount	$ 0.48	$ 1.95	$ 1.18
Earnings Per Share (Textual) [Abstract]
Options to purchase, shares	1,585,594	1,375,281	1,361,779	1,289,194
Options to purchase, exercise price	$ 33.13	$ 32.46	$ 29.67	$ 29.72
Stock options not included in the computation of diluted EPS	1,300,000	800,000	600,000