Commitments and Contingencies - Purchase Commitments (Details) $ in Millions	Jun. 30, 2017 USD ($)
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase commitments, total	$ 309.1
Affiliated
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase commitments, total	$ 79.9

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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