Schedule I Financial Information Schedule I Financial Information - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Condensed Financial Statements, Captions [Line Items]
Cash payments made for reorganization items	$ 0
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash payments made for reorganization items	$ 0

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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