Guarantor Financial Statements (Unaudited) Guarantor Financial Statements (Details)	Mar. 31, 2018
FM O&G LLC Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	10000.00%

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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