Commitments (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Other Commitments [Line Items]
Letters of Credit Outstanding, Amount	$ 92.6
Revolving Credit Facility [Member]
Other Commitments [Line Items]
Letters of Credit Outstanding, Amount	49.9
Cash and Cash Equivalents [Member]
Other Commitments [Line Items]
Pledged Assets, Not Separately Reported, Other	4.3
Guarantee Type, Other [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	15.5
Performance Guarantee [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	29.9
Indemnification Agreement [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 433.0