Commitments (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013
Other Commitments [Line Items]
Letters of Credit Outstanding, Amount	$ 92.9
Line of Credit [Member]
Other Commitments [Line Items]
Letters of Credit Outstanding, Amount	42.2
Cash and Cash Equivalents [Member]
Other Commitments [Line Items]
Pledged Assets, Not Separately Reported, Other	4.8
Guarantee Type, Other [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	16.0
Performance Guarantee [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	35.9
Indemnification Agreement [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 360.0