Revolving Credit Facility and Long-Term Debt - Financial Covenants (Details)	12 Months Ended
Dec. 31, 2017 USD ($) quarter
Debt Instrument [Line Items]
Number of consecutive quarters for EBITDA to fixed charges ratio covenants \| quarter	4
Credit Agreement
Debt Instrument [Line Items]
Consolidated EBITDA	$ 1.25
Consolidated Net Income	0
Facility Capital Expenditures	$ 30,000,000
July 1, 2017 through December 31, 2017 \| Credit Agreement
Debt Instrument [Line Items]
Consolidated Total Leverage Ratio	3.75
January 1, 2018 through March 31, 2018 \| Credit Agreement
Debt Instrument [Line Items]
Consolidated Total Leverage Ratio	3.5
April 1, 2018 and thereafter \| Credit Agreement
Debt Instrument [Line Items]
Consolidated Total Leverage Ratio	3.25

Line of Credit Facility, Covenant Terms, Consolidated EBITDA to Fixed Charges Ratio, Number of Consecutive Quarters

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- Definition

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

+ References

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- Definition

Line of Credit Facility, Covenant Terms, Consolidated Ebitda To Fixed Charges Ratio, Minimum1

+ 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

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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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