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

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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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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, 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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Note 14 - Long-term Debt and Credit Arrangements (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 26, 2020	Mar. 25, 2020	Dec. 31, 2019	Nov. 30, 2019	Jul. 29, 2019	Mar. 31, 2019	May 31, 2018
Long-Term Debt, Maturity, Year One	$ 6,300
Long-term Debt, Maturities, Repayments of Principal in Year Two	8,500
Long-term Debt, Maturities, Repayments of Principal in Year Three	8,500
Long-term Debt, Maturities, Repayments of Principal in Year Four	142,300
Long-term Debt, Maturities, Repayments of Principal in Year Five	231,100
Long-term Debt, Maturities, Repayments of Principal after Year Five	7,900
Long-term Debt, Current Maturities, Total	8,253			$ 8,244			$ 47,281
Long-term Debt, Excluding Current Maturities, Total	355,911			356,108			333,290
Additional Paid-in Capital [Member] \| Warrants Issued With 2.75% Convertible Notes [Member]
Warrants and Rights Outstanding	11,200			11,200
Additional Paid-in Capital [Member] \| Hedge Option [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	$ 34,700			$ 36,300
Debt Instrument, Face Amount					$ 230,000
Debt Instrument, Interest Rate, Stated Percentage				2.75%	2.75%
Long-term Debt, Gross	195,300			$ 193,700
The Credit Agreement [Member]
Letters of Credit Outstanding, Amount	$ 31,200
Consolidated Leverage Ratio, Actual	1.97
Consolidated Leverage Ratio, Covenant Maximum	3.25
Consolidated Interest Coverage Ratio, Actual	9.02
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	3.00%
Debt Instrument, Interest Rate, Effective Percentage	4.45%
The Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	0.75%
The Credit Agreement [Member] \| Base Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Debt Instrument, Interest Rate, Effective Percentage	5.25%
The Credit Agreement [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 275,000	$ 350,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 218,800
Long-term Line of Credit, Total	25,000
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	$ 129,400			$ 131,300			136,900
The 2019 Notes [Member] \| Senior Notes [Member]
Debt Instrument, Face Amount						$ 40,000	$ 40,000
Debt Instrument, Interest Rate, Stated Percentage							6.11%