Selected Quarterly Data (Unaudited) (Details) $ / shares in Units, $ in Millions	3 Months Ended									12 Months Ended
	May 31, 2020 USD ($) $ / shares	Feb. 29, 2020 USD ($) $ / shares	Nov. 30, 2019 USD ($) $ / shares	Aug. 31, 2019 USD ($) $ / shares	May 31, 2019 USD ($) $ / shares	Feb. 28, 2019 USD ($) $ / shares	Nov. 30, 2018 USD ($) $ / shares	Aug. 31, 2018 USD ($) $ / shares	Feb. 28, 2018 USD ($)	May 31, 2020 USD ($) facility $ / shares	May 31, 2019 USD ($) $ / shares	May 31, 2018 USD ($) $ / shares
Sales	$ 416.5	$ 553.1	$ 560.9	$ 541.5	$ 562.7	$ 529.5	$ 493.3	$ 466.3		$ 2,072.0	$ 2,051.8	$ 1,748.3
Operating income (loss)	(14.9)	5.3	28.1	22.8	29.3	29.8	16.8	22.4		41.3	98.3	86.0
Income (Loss) from continuing operations	(15.0)	2.6	20.1	17.1	26.6	27.4	11.2	18.9		24.8	84.1	73.7
Loss from discontinued operations	(1.5)	(0.3)	(5.9)	(12.7)	(3.8)	(64.8)	(4.2)	(3.8)		(20.4)	(76.6)	(58.1)
Net income (loss)	$ (16.5)	$ 2.3	$ 14.2	$ 4.4	$ 22.8	$ (37.4)	$ 7.0	$ 15.1		$ 4.4	$ 7.5	$ 15.6
Earnings (Loss) per share - basic:
Continuing operations | $ / shares	$ (0.43)	$ 0.08	$ 0.58	$ 0.49	$ 0.77	$ 0.79	$ 0.32	$ 0.54		$ 0.71	$ 2.42	$ 2.14
Discontinued operations | $ / shares	(0.04)	(0.01)	(0.17)	(0.37)	(0.11)	(1.87)	(0.12)	(0.11)		(0.59)	(2.22)	(1.70)
Earnings (Loss) per share - basic | $ / shares	(0.47)	0.07	0.41	0.12	0.66	(1.08)	0.20	0.43		0.12	0.20	0.44
Earnings (Loss) per share - diluted:
Continuing operations | $ / shares	(0.43)	0.07	0.57	0.49	0.76	0.78	0.32	0.54		0.71	2.40	2.11
Discontinued operations | $ / shares	(0.04)	(0.01)	(0.17)	(0.36)	(0.11)	(1.86)	(0.12)	(0.11)		(0.58)	(2.19)	(1.70)
Earnings (Loss) per share - diluted | $ / shares	$ (0.47)	$ 0.06	$ 0.40	$ 0.13	$ 0.65	$ (1.08)	$ 0.20	$ 0.43		$ 0.13	$ 0.21	$ 0.41
Contracts charge										$ 31.3
Impairment charges										11.0
Closure costs										$ 4.9
Number of facilities closed | facility										2
Workforce actions including severance and furlough costs										$ 5.0
COCO
Earnings (Loss) per share - diluted:
Impairment charges									$ 9.8
PBH contracts
Earnings (Loss) per share - diluted:
Contracts charge	$ 6.6	$ 24.7								$ 31.3
Held for sale or Disposed | COCO
Earnings (Loss) per share - diluted:
Impairment charges				$ 11.8		$ 74.1