Long-term Debt - Receivables Facility (Details) (Receivables Facility [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Receivables Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Unused Borrowing Capacity, Fee percentage			0.40%	0.45%
Secured Debt	$ 55.0		$ 55.0		$ 18.0
Secured debt, Maximum Borrowing Capacity	105.0		105.0
Debt Instrument, Basis Spread on Variable Rate			1.20%	1.50%
Receivables facility debt available but not utilized	36.0		36.0		51.9
Receivables facililty, debt aggregate costs	$ 0.4	$ 0.3	$ 1.1	$ 0.8
Average liquidation period, Receivables pool	1.6		1.6
Average discount rate, Receivables facility	1.80%		1.80%