Debt (The Receivables Facility) (Narrative) (Details) (USD $)					3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 Receivables Facility	Dec. 31, 2012 Receivables Facility	Mar. 31, 2013 Revolving Credit Facility Revolving Facility
Debt Instrument [Line Items]
Receivables Facility maximum borrowing capacity			$ 400,000,000
Debt instrument, basis spread on variable rate			0.75%
Commitment fee percentage					35 basis points
Securitized accounts receivable	455,700,000	556,500,000
Short-term borrowings	$ 485,486,000	$ 298,987,000	$ 300,000,000	$ 180,000,000
Interest rate on borrowings			0.97%