Income Taxes - Operating Loss carryforward (Details) - USD ($) $ in Millions	May 31, 2020	May 26, 2019
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 214.2	$ 213.7
Operating loss carryforwards valuation allowance	155.6
Business Acquisition [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	108.3
State and Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	28.2
Capital Loss Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	65.8
Other Valuation Allowance [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	11.9
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards valuation allowance	143.5
Foreign [Member] | State and Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	143.5
Foreign [Member] | No Expiration Date [Member] | State and Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	119.0
Foreign [Member] | Expiration Dates in Year One and Two [Member] | State and Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	3.7
Foreign [Member] | Expiration Dates in Year Three and Beyond [Member] | State and Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	20.8
State [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards valuation allowance	$ 12.1