Fixed charge coverage ratio.

No definition available.

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Lease expiration year.

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No definition available.

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Line of credit facility optional increase capacity.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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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Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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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.

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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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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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-Subparagraph (SX 210.4-08.(f))
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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.

+ References

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Long-Term Debt (Narrative) (Details) - USD ($)		3 Months Ended	12 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 30, 2016	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 2014	Jan. 31, 2011
Debt Instrument [Line Items]
Revolving credit facility			$ 104,111,000
Letters of credit outstanding			63,339,000
Letter of credit remaining borrowing capacity			47,522,000
7.375% senior notes			272,998,000	$ 271,998,000
Purchases of property and equipment			83,798,000	74,455,000	$ 91,910,000
Amortization of deferred financing fees			$ 2,438,000	$ 1,729,000	$ 1,453,000
Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount						$ 25,000,000
Debt instrument, interest rate, stated percentage			7.375%
Vessels and Ancillary Equipment [Member]
Debt Instrument [Line Items]
Purchases of property and equipment		$ 15,569,000
Operating leases expiration year			2023
7.375% Senior Notes Due In 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 275,000,000
Debt instrument, interest rate, stated percentage			7.375%
7.375% senior notes							$ 250,000,000
Maturity date			Mar. 01, 2020
7.375% Senior Notes Due In 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 275,000,000
Debt instrument, interest rate, stated percentage			7.375%
Maturity date			Feb. 01, 2019
5.75% Senior Notes Due In 2023 [Member] \| Vessels and Ancillary Equipment [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		5.75%
If Redeemed In 2015 [Member] \| 7.375% Senior Notes Due In 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage			103.70%
If Redeemed In 2016 [Member] \| 7.375% Senior Notes Due In 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage			101.80%
If Redeemed After 2016 [Member] \| 7.375% Senior Notes Due In 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage			100.00%
Maximum [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	$ 250,000,000
Line of credit facility optional increase capacity	$ 100,000,000
Revolving credit facility, maturity date			Dec. 30, 2019
Revolving credit facility, Description			The Credit Agreement matures on December 30, 2019; provided that the maturity date shall be accelerated to November 3, 2018 if the Company fails to refinance its unsecured senior notes that mature February 1, 2019. The refinanced notes must have a maturity on or after March 31, 2020
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]
Payment of revolving 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 bear interest fixed rate	4.655%