CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE (LOSS) INCOME (Parenthetical) (Parentheticals) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 01, 2020	Jan. 26, 2019	Feb. 01, 2020	Jan. 26, 2019
Statement of Comprehensive Income [Abstract]
Change in pension benefit obligation, tax (benefit)	$ 2.4	$ 0.0	$ 2.6	$ 0.0
Change in fair value of swap agreements, tax (benefit)	$ (1.3)	$ (3.9)	$ (2.5)	$ (4.0)

Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580

Name:	us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration