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Debt Instrument, Issue Price Percentage

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Debt Instrument Redemption Price Call Premium

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Percentage of Notes Registered under the Securities Act of 1933

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Restrictive Covenants Exception for Dividend or Distribution Amount during fiscal year

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Restrictive Covenants Exception for total Dividend Payment and other Restricted Payments

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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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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Start date of debt instrument redemption period, in CCYY-MM-DD format.

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Percentage of principal amount of debt redeemed.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Gross amount of debt extinguished.

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Aggregate amount of interest paid or due on all long-term debt.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Long-Term Debt - Additional Information (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	Aug. 25, 2019	Jun. 23, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Aug. 26, 2019	Dec. 31, 2018	Sep. 19, 2017
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 200,000		$ 200,000			$ 200,000
Long-term debt			199,225		199,225			$ 199,096
6.75% Senior Secured Notes [Member] \| Senior Secured Notes
Debt Instrument [Line Items]
Private placement date		Jun. 23, 2017
Debt Instrument, Face Amount		$ 200,000
Interest rate		6.75%
Debt Issuance Costs, Gross		$ 4,300
Interest expense on note			3,400	$ 3,400	6,800	$ 6,800
Debt Instrument, Issue Price Percentage		100.00%
Percentage of Notes Registered under the Securities Act of 1933									99.80%
8.75% Senior Secured Notes [Member] \| Senior Secured Notes
Debt Instrument [Line Items]
Interest rate		8.75%
Extinguishment of Debt, Amount		$ 120,000
Oppenheimer [Member] \| 6.75% Senior Secured Notes [Member] \| Senior Secured Notes
Debt Instrument [Line Items]
Debt Issuance Costs, Gross		3,000
Third Party [Member] \| 6.75% Senior Secured Notes [Member] \| Senior Secured Notes
Debt Instrument [Line Items]
Debt Issuance Costs, Gross		$ 1,300
Maximum [Member] \| 6.75% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Restrictive Covenants Exception for Dividend or Distribution Amount during fiscal year					20,000
Restrictive Covenants Exception for total Dividend Payment and other Restricted Payments			$ 10,000		$ 10,000
Forecast [Member]
Debt Instrument [Line Items]
Annual Interest Costs Reduction as a result of Debt Redemption	$ 3,800
Debt Instrument Redemption Price Call Premium	103.375%
Payment for Debt Extinguishment or Debt Prepayment Cost	$ 1,700
Long-term Debt, Gross							$ 150,000
Repayments of Secured Debt	$ 50,000
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	25.00%
Debt Instrument, Redemption Period, Start Date	Aug. 25, 2019