Revolving Credit Facility and Long-Term Debt - Financial Covenants (Details) - Credit Agreement	6 Months Ended
Jun. 30, 2018 USD ($)
Debt Instrument [Line Items]
Consolidated EBITDA	1.25
Consolidated Net Income	$ 0
Facility Capital Expenditures	$ 30,000,000
January 1, 2018 and thereafter
Debt Instrument [Line Items]
Consolidated Total Leverage Ratio	3.5

Line of Credit Facility, Covenant Terms, Facility Capital Expenditures, Next Twelve Months, Maximum

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- Definition

Line of Credit Facility, Covenant Terms, Consolidated Ebitda To Fixed Charges Ratio, Minimum2

+ References

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- Definition

Line of Credit Facility, Covenant Terms, Consolidated Net Income, Minimum

+ References

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- Definition

Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Maximum

+ References

No definition available.

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- Definition

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.

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