Basis of Presentation - Accounting Pronouncements Adopted (Details) - ASU 2016-01 - Investments $ in Millions	Apr. 29, 2018 USD ($)
Retained Earnings
Accounting pronouncements adopted in fiscal 2019
Reclassification of net unrealized gains, before tax	$ 2.1
Reclassification of tax expense	0.5
Accumulated Other Comprehensive Income (Loss)
Accounting pronouncements adopted in fiscal 2019
Reclassification of net unrealized gains, before tax	(2.1)
Reclassification of tax expense	$ (0.5)

Amount of the cumulative effect on retained earnings before related income tax effect.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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Amount of the related income tax effect of a cumulative effect on retained earnings.

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