Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 26, 2019	May 27, 2018
Statement of Comprehensive Income [Abstract]
Change in fair value of marketable securities, tax	$ 0.0	$ 0.0	$ 0.0
Other comprehensive income (loss), unrecognized gain (loss) on derivatives, net of taxes	(0.3)	(0.1)	0.0
Net unamortized gain (loss) arising during period, including amortization of unrecognized net actuarial loss, tax	$ 30.8	$ (6.4)	$ (0.7)

Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569643-111683

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