Note 5 - Long-term Debt (Details Textual) - USD ($) $ in Thousands		3 Months Ended
May 17, 2019	Mar. 28, 2020
Debt Instrument, Face Amount		$ 193,750
Credit Agreement, May 17, 2019 [Member] \| Revolving Credit Facility [Member]
Debt Instrument, Term (Year)	5 years
Line of Credit Facility, Maximum Borrowing Capacity	$ 75,000
Proceeds from Lines of Credit, Total		$ 50,000
Debt Instrument, Interest Rate, Effective Percentage		3.07%
Line of Credit Facility, Commitment Fee Percentage		0.20%
Credit Agreement, May 17, 2019 [Member] \| Secured Term Loan [Member]
Debt Instrument, Term (Year)	5 years
Debt Instrument, Face Amount	$ 175,000
Debt Instrument, Periodic Payment, Total		$ 4,400
Debt Instrument, Interest Rate, Effective Percentage		2.17%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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