Asset Write Down (Details) $ / shares in Units, $ in Millions	12 Months Ended
	May 31, 2022 USD ($) fairs $ / shares	May 31, 2021 USD ($) fairs	May 31, 2020 USD ($)
Class of Stock [Line Items]
Impairment on right-of-use assets		$ 7.0
Impairment expense on other long-lived assets		1.5
Asset impairment expense		2.6
Provision for losses on inventory	$ 27.7	$ 36.6	$ 34.3
Number of book fair closed | fairs	13	13
Number of book fairs total | fairs	54	54
Loss on Assets Held for Sale, Impact On Earnings Per Share, Basic | $ / shares	$ 0.33
Loss on Assets Held for Sale, Impact On Earnings Per Share, Diluted | $ / shares	$ 0.32
Non cash write off related to asset impairments and write downs	$ 0.4	$ 11.1	$ 40.6
Leaseholds and Leasehold Improvements
Class of Stock [Line Items]
Asset Impairment Charges		$ 8.5
Class A Stock
Class of Stock [Line Items]
Impact on earnings per share (USD per share) | $ / shares	$ 0.24