Long-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Long-Term Debt [Abstract]
Revolving credit facility period, years	5 years
Revolving credit facility	$ 350
Revolving credit facility, rate description	LIBOR plus 125 basis points
Line of credit facility, basis points above LIBOR	125
Revolving credit facility, interest rate description	floating interest rate
Line of credit expansion feature	150
Standby letters of credit issued	29.2
Unused lines of credit	$ 320.8
Effective rate on Notes	6.875%