Long-Term Debt (Narrative) (Details)	May 31, 2018 USD ($)	Dec. 29, 2018 USD ($)
Debt Instrument [Line Items]
Debt issuance costs current		$ 400,000
Debt issuance cost noncurrent		1,500,000
Revolving commitment
Debt Instrument [Line Items]
Outstanding revolving credit facility		150,000,000
Maximum line of credit facility borrowing capacity		450,000,000
Private Placement Notes
Debt Instrument [Line Items]
Debt issuance cost noncurrent		$ 600,000
Outstanding revolving credit facility	$ 100,000,000
Fixed rate notes due in 2025 with an interest rate of 4.22%
Debt Instrument [Line Items]
Debt instrument term	7 years
Revolving credit facility	$ 50,000,000
Fixed interest rate	4.22%	4.22%
Fixed rate notes due in 2028 with an interest rate of 4.40%
Debt Instrument [Line Items]
Debt instrument term	10 years
Revolving credit facility	$ 50,000,000
Fixed interest rate	4.40%	4.40%
Revolving commitment
Debt Instrument [Line Items]
Interest coverage ratio		4
Consolidated leverage ratio		3.5

Debt Instrument, Covenant, Ratio of Interest Coverage to Earnings for the Last Four Fiscal Quarters

No definition available.

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- Definition

Debt Instrument, Covenant, Ratio of Leverage to Earnings for the Last Four Fiscal Quarters

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

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.

+ References

No definition available.

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- 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

Amount, before accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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-Paragraph 3
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Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

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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-Paragraph 1
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- 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.

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