Segment Information - Schedule of Segment Reporting Information (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2024	May 31, 2023	May 31, 2022
Segment Reporting Information [Line Items]
Revenues	$ 1,589.7	$ 1,704.0	$ 1,642.9
Total revenue, excluding rental income	1,580.0	1,704.0	1,642.9
Operating Income (Loss)	14.5	106.3	97.4
Depreciation and amortization	93.2	89.7	91.3
Segment assets	1,671.2	1,866.7	1,940.8
Children's Book Publishing and Distribution
Segment Reporting Information [Line Items]
Revenues	955.2	1,038.0	946.5
Education Solutions
Segment Reporting Information [Line Items]
Revenues	351.2	386.6	393.6
International Segment
Segment Reporting Information [Line Items]
Revenues	273.6	279.4	302.8
Operating Segments | Children's Book Publishing and Distribution
Segment Reporting Information [Line Items]
Revenues	955.2	1,038.0	946.5
Operating Income (Loss)	112.1	143.4	115.3
Depreciation and amortization	22.5	22.9	24.9
Segment assets	565.1	599.9	559.4
Operating Segments | Education Solutions
Segment Reporting Information [Line Items]
Revenues	351.2	386.6	393.6
Operating Income (Loss)	15.8	58.4	81.8
Depreciation and amortization	23.6	20.2	15.1
Segment assets	242.0	290.8	289.4
Operating Segments | International Segment
Segment Reporting Information [Line Items]
Revenues	273.6	279.4	302.8
Operating Income (Loss)	(6.9)	(3.6)	3.3
Depreciation and amortization	5.3	5.1	6.2
Segment assets	256.0	260.0	258.3
Corporate, Non-Segment | Overhead
Segment Reporting Information [Line Items]
Operating Income (Loss)	(106.5)	(91.9)	(103.0)
Depreciation and amortization	41.8	41.5	45.1
Segment assets	$ 608.1	$ 716.0	$ 833.7