Stock Compensation Plans (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended					12 Months Ended							12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008	May 06, 2005	Dec. 31, 2012 Stock Only Stock Appreciation Rights	Dec. 31, 2008 Stock Only Stock Appreciation Rights	Dec. 31, 2007 Stock Only Stock Appreciation Rights	Dec. 31, 2012 Restricted Stock Awards	Dec. 31, 2012 Performance Share Units	Dec. 31, 2011 Performance Share Units	Dec. 31, 2010 Performance Share Units	Dec. 31, 2012 Performance Share Units Executive Officer	Dec. 31, 2012 Employee Stock	May 06, 2005 Prior Plan
Stock Compensation Plans (Textual) [Abstract]
Number of shares authorized to grant under LT Plan					400,000
Number of shares remained available	409,000													228,000	426,000
Number of additional shares available under LT Plan				500,000
Maximum term for options granted	10 years
Compensation expense recognized	$ 4.0	$ 4.1	$ 2.6
Term of granting options to directors and management personnel							5 years	5 years
General vesting period of options granted							3 years	3 years	3 years
Historical volatility period						5 years
Number of shares issued									69,232				96,464
SOSARs granted, Shares									69,000	97,000
Total unrecognized compensation cost									$ 2.2	$ 1.5
Period for recognition of compensation cost									2 years	2 years
Period for right to receive shares dependent on the achievement of specific performance results										3 years
Percentage of maximum amount available for issuance										100.00%	100.00%	10.00%
Term of Treasury issues														1 year