Fair Value Measurements - Schedule of financial assets measured at fair value on a recurring basis (Details) - Estimate Of Fair Value Fair Value Disclosure Member $ in Millions	Jun. 25, 2022 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	$ 64.1
Municipal Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	7.8
Corporate Debt Securities Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	41.8
Money Market Funds Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	12.1
Certificates of Deposit Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	2.4
Level 1 Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	12.1
Level 1 Member \| Municipal Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0.0
Level 1 Member \| Corporate Debt Securities Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0.0
Level 1 Member \| Money Market Funds Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	12.1
Level 1 Member \| Certificates of Deposit Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0.0
Level 2 Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	52.0
Level 2 Member \| Municipal Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	7.8
Level 2 Member \| Corporate Debt Securities Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	41.8
Level 2 Member \| Money Market Funds Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0.0
Level 2 Member \| Certificates of Deposit Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	2.4
Level 3 Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	0.0
Level 3 Member \| Municipal Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0.0
Level 3 Member \| Corporate Debt Securities Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0.0
Level 3 Member \| Money Market Funds Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0.0
Level 3 Member \| Certificates of Deposit Member
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 0.0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

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

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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