Derivative Financial Instruments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Feb. 29, 2012	Jun. 30, 2012 Interest Rate Swap [Member]	Feb. 29, 2012 Interest Rate Swap [Member]	Dec. 31, 2011 Intangible and Other Long Term Assets [Member]
Derivatives, Fair Value [Line Items]
Adjustment Interval of Variable Rate on Interest Rate Swap	90
Derivative asset	$ 1.0					$ 1.9
Selling of interest rate swap			1.2	1.2
Interest income (expense) related to the ineffectiveness associated with the fair value hedge	1.0	1.2
Interest rate swap agreement for notional amount	$ 100		$ 150		$ 150