Stock-Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		0 Months Ended	3 Months Ended		0 Months Ended	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Apr. 17, 2013 Nonvested Stock Award [Member]	Mar. 31, 2013 Nonvested Stock Award [Member] Minimum [Member]	Mar. 31, 2013 Nonvested Stock Award [Member] Maximum [Member]	Apr. 17, 2013 Stock Appreciation Rights (SARs) [Member]	Mar. 31, 2013 Stock Appreciation Rights (SARs) [Member]	Mar. 31, 2013 Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Share Awards Granted in Period	70,003		184,546
SARs granted in period	0					214,233
Allocated Share-based Compensation Expense	$ 1.2	$ 1.4
Vesting period (in years)				4 years	7 years		4 years	3 years
Contractual terms of stock options granted (in years)							10 years	10 years