Fixed charge coverage ratio.

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- Definition

Interest margin applicable rate.

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No definition available.

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- Definition

Line of credit facility optional increase capacity.

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No definition available.

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- Definition

Number of days prior to scheduled maturity date.

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No definition available.

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- Definition

Owned domestic subsidiaries percent.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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

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- Definition

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

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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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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Long-Term Debt (Narrative) (Details) - USD ($)		1 Months Ended	6 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	May 03, 2019	May 31, 2017	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Revolving credit facility			$ 0	$ 11,500,000
Letters of credit outstanding			36,747,000
Letter of credit remaining borrowing capacity			162,761,000
Availability under credit agreement suppressed			$ 492,000
8.000% Senior Notes Due in 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 325,000,000
Debt instrument, interest rate, stated percentage		8.00%
Maturity date		May 15, 2022
Owned Domestic Subsidiaries Percent		100.00%
Minimum [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio	1.10%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 200,000,000
Line of credit facility optional increase capacity	$ 100,000,000
Revolving credit facility, maturity date			May 03, 2024
Description of refinanced notes maturity after the maturity date			The refinanced notes must have a maturity on or after the date that is 180 days after the maturity date of the Amended Credit Agreement.
Number of days prior to scheduled maturity date			91 days
Revolving Credit Facility [Member] \| Domestic Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Interest margin applicable	0.50%
Revolving Credit Facility [Member] \| Daily LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Revolving Credit Facility [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Interest margin applicable	1.50%
Revolving Credit Facility [Member] \| Minimum [Member] \| Domestic Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Revolving Credit Facility [Member] \| Minimum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Revolving Credit Facility [Member] \| Maximum [Member] \| Domestic Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Revolving Credit Facility [Member] \| Maximum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%