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

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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
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- Definition

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

+ References

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Balance Type:	na
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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

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
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+ Details

Name:	us-gaap_LongTermDebt
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Balance Type:	debit
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

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- Definition

Represents the maximum amount of the guarantees available through letters of credit.

+ References

No definition available.

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Debt - Credit Agreement (Details) - USD ($) $ in Millions		9 Months Ended
Debt - Credit Agreement (Details) - USD ($) $ in Millions	Feb. 12, 2016	Sep. 29, 2019	Jun. 30, 2019	Sep. 30, 2018	Jul. 01, 2018
Credit Agreement
Stand-by letters of credit outstanding			$ 25.8		$ 25.8
Term Loan due February 2021
Credit Agreement
Repayment of debt		$ 22.5
Letters of credit
Credit Agreement
Term of debt		1 year
5.05% Senior notes due 2020
Credit Agreement
Interest rate (as a percent)		5.05%
Credit Agreement
Credit Agreement
Term of debt	5 years
Sublimit on letters of credit	$ 100.0
Senior unsecured revolving credit facility
Credit Agreement
Borrowing capacity	$ 500.0
Amount drawn		$ 37.0
Interest rate on revolving credit facility (as a percent)		3.11%
Term loan facility \| Term Loan due February 2021
Credit Agreement
Term of debt	5 years
Face amount	$ 300.0
Interest rate on term loan facility (as a percent)		3.43%
Amount drawn		$ 300.0
Borrowings outstanding		$ 232.5		$ 260.6