Capital expenditures by credit parties.

No definition available.

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- Definition

Face value of senior notes issued, percentage.

+ References

No definition available.

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Fixed charge coverage ratio.

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Fixed charge coverage ratio trigger for maximum availability under credit agreement for five consecutive days.

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Fixed charge coverage ratio trigger for maximum availability under credit agreement for one day.

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- Definition

Line of credit facility optional increase capacity.

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No definition available.

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Percentage of companies domestic subsidiaries that guaranteed obligation under senior notes.

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No definition available.

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Redemption of notes.

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No definition available.

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Amount of amortization expense attributable to debt issuance costs.

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

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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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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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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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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 fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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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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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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- Definition

Amount of operating lease expense. Excludes sublease income.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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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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Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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Long-Term Debt (Narrative) (Details) - USD ($)		1 Months Ended		12 Months Ended			24 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 30, 2016	Feb. 28, 2018	May 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Debt Instrument [Line Items]
Maximum availability of earnings under credit agreement for five consecutive days				$ 31,250,000			$ 31,250,000
Maximum availability of earnings under credit agreement for one day				25,000,000			25,000,000
Revolving credit facility				11,500,000			11,500,000
Letters of credit outstanding				37,749,000			37,749,000
Letter of credit remaining borrowing capacity				174,555,000			174,555,000
Line of credit facility current borrowing capacity				$ 26,196,000			$ 26,196,000
Net proceeds from issuance					$ 325,000,000
Percentage of companies domestic subsidiaries that guaranteed obligation under senior notes				100.00%
Amortization of deferred financing fees				$ 3,504,000	$ 3,280,000	$ 2,438,000
Senior Notes [Member]
Debt Instrument [Line Items]
Face value of senior notes issued, percentage				100.00%			100.00%
Net proceeds from issuance				$ 321,653,000
Vessels and Ancillary Equipment [Member]
Debt Instrument [Line Items]
Net proceeds from sale-leaseback of a vessel yielding		$ 4,500,000
8.000% Senior Notes Due in 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 325,000,000	$ 325,000,000			$ 325,000,000
Debt instrument, interest rate, stated percentage			8.00%	8.00%			8.00%
Maturity date			May 15, 2022	May 15, 2022
7.375% Senior Notes Due In 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				$ 275,000,000			$ 275,000,000
Debt instrument, interest rate, stated percentage				7.375%	7.375%		7.375%
Maturity date				Feb. 28, 2019
Redemption of notes				$ 282,638,000			$ 282,638,000
Maximum [Member]
Debt Instrument [Line Items]
Expenses related to buy-out operating leases				$ 20,000,000
Capital expenditures by credit parties							$ 135,000,000
Fixed charge coverage ratio	1.10%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 250,000,000
Line of credit facility optional increase capacity	$ 100,000,000
Revolving credit facility, maturity date				Dec. 30, 2019
Revolving Credit Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Revolving Credit Facility [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unused fee percentage	0.375%
Revolving Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Revolving Credit Facility [Member] \| Maximum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Unused fee percentage	0.25%
Revolving Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Revolving Credit Facility [Member] \| Minimum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.50%
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 250,000,000
Swingline Loans [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	25,000,000
Prior Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Repayments of lines of credit	$ 199,000,000
Prior Revolving Credit Agreement [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Prior Revolving Credit Agreement [Member] \| Maximum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.50%
Prior Revolving Credit Agreement [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Prior Revolving Credit Agreement [Member] \| Minimum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Prior Secured Term Loan Facility [Member]
Debt Instrument [Line Items]
Payment of secured term loan	$ 50,000,000
Term loan facility bore interest fixed rate	4.655%