Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Name:	us-gaap_GrossProfit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

General General (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
General General (Details) - USD ($) $ in Millions	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019	Dec. 27, 2019
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Gross profit	$ 67.3	$ 76.2	$ 214.5	$ 268.9
Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Gross profit		$ 1.5		$ 4.6	$ 5.8