Lease Commitments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2018	Dec. 31, 2017	Dec. 25, 2016
Leases [Abstract]
Sublease income on operating leases	$ 4.3
Operating Leases
2019	16.5
2020	12.0
2021	9.6
2022	8.1
2023	7.9
Thereafter	63.1
Total future minimum lease payments	117.2
Gross rent expense under operating leases	23.7	$ 18.6	$ 18.7
Sublease income	3.3	3.4	3.3
Accrual for excess facilities
Accrual for excess facilities - beginning balance	3.3	4.0
Adjustment of excess facility accrual	0.0	0.0
Cash payments	(0.9)	(0.7)
Accrual for excess facilities - ending balance	2.4	3.3	$ 4.0
Deferred rent	$ 4.4	$ 3.0

Accrual for Unused Facilities

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- Definition

Accrual for Unused Facilities, Accrual Adjustment

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No definition available.

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Accrual for Unused Facilities, Cash Payments

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No definition available.

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- Definition

Accrual for Unused Facilities [Roll Forward]

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No definition available.

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- Definition

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
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- References

No definition available.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

+ References

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- Definition

The total amount of sublease rental income recognized during the period that reduces the entity's rent expense incurred under operating leases.

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