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Percentage of principal balance outstanding that is required to be periodically paid.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The carrying value as of the balance sheet date of the current and noncurrent portions 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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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. 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 long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Note 14 - Long-term Debt and Credit Arrangements (Details Textual) - USD ($) $ in Thousands		6 Months Ended
	May 04, 2020	Jun. 30, 2020	Mar. 26, 2020	Mar. 25, 2020	Dec. 31, 2019	Nov. 30, 2019	Jul. 29, 2019	Jun. 30, 2019	May 31, 2018
Long-Term Debt, Maturity, Remainder of Fiscal Year		$ 4,200
Long-Term Debt, Maturity, Year One		8,500
Long-Term Debt, Maturity, Year Two		8,500
Long-Term Debt, Maturity, Year Three		192,300
Long-Term Debt, Maturity, Year Four		231,100
Long-Term Debt, Maturity, after Year Four		7,900
Long-term Debt, Current Maturities, Total		8,253			$ 8,244			$ 48,397
Long-term Debt, Excluding Current Maturities, Total		405,770			356,108			366,896
Additional Paid-in Capital [Member] \| Warrants Issued With 2.75% Convertible Notes [Member]
Warrants and Rights Outstanding		11,200			11,200
Hedge Option [Member] \| Additional Paid-in Capital [Member]
Derivative Liability, Total		$ 27,900			27,900
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		2.76%
The 2.75% Convertible Notes [Member]
Debt Instrument, Convertible, Carrying Amount of Equity Component		$ 33,100			$ 36,300
Debt Instrument, Face Amount						$ 230,000
Debt Instrument, Interest Rate, Stated Percentage					2.75%	2.75%
Long-term Debt, Gross		196,900			$ 193,700
Debt Instrument, Convertible, Additional Interest Rate	0.50%
The Credit Agreement [Member]
Letters of Credit Outstanding, Amount		$ 31,200
Consolidated Leverage Ratio, Actual		2.27
Consolidated Leverage Ratio, Covenant Maximum		3.25
Consolidated Interest Coverage Ratio, Actual		7.89
Debt Instrument, Covenant, Minimum Consolidated Interest Coverage Ratio		4.00
The Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Debt Instrument, Interest Rate, Effective Percentage		3.75%
The Credit Agreement [Member] \| Base Rate [Member]
Debt Instrument, Interest Rate, Effective Percentage		5.25%
The Credit Agreement [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 168,800
Long-term Line of Credit, Total		$ 75,000
The Credit Agreement [Member] \| Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		0.75%
The Credit Agreement [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 275,000	$ 350,000
The Credit Agreement [Member] \| Term Loan [Member]
Debt Instrument, Periodic Payment, Principal Balance Percentage									1.25%
Debt Instrument, Face Amount									$ 150,000
Long-term Debt, Current Maturities, Total		$ 7,500			7,500			7,500
Long-term Debt, Excluding Current Maturities, Total		$ 127,500			$ 131,300			135,000
The 2019 Notes [Member] \| Senior Notes [Member]
Debt Instrument, Face Amount							$ 40,000	$ 40,000
Debt Instrument, Interest Rate, Stated Percentage								6.11%