Summary of Charges Recorded in Connection with Restructuring by Reportable Segment (Parenthetical) (Detail)	12 Months Ended
	May 31, 2020 USD ($) Position	May 31, 2019 USD ($) Position Executive	May 31, 2018 USD ($) Position
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 33,108,000	$ 42,310,000	$ 17,514,000
2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	33,108,000	42,310,000	17,514,000
2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 19,747,000	$ 32,519,000	$ 9,957,000
Construction Products Segment | 2020 MAP to Growth Related to Current Elimination | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position	112	109	27
Construction Products Segment | 2020 MAP to Growth Plan Related to Legal Function
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position		1
Restructuring charges		$ 200,000
Construction Products Segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 8,726,000	11,598,000	$ 4,187,000
Construction Products Segment | 2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	6,866,000	9,459,000	1,769,000
Performance Coatings Segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 9,094,000	$ 9,839,000	$ 400,000
Performance Coatings Segment | 2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position	161	114	1
Restructuring charges	$ 6,973,000	$ 6,012,000	$ 400,000
Corporate/Other Segment
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position	2
Corporate/Other Segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 1,227,000	9,984,000	2,136,000
Corporate/Other Segment | 2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	1,227,000	$ 9,984,000	2,136,000
Number of corporate executives | Executive		2
Corporate/Other Segment | 2020 MAP to Growth | Vesting Equity Awards
Restructuring Cost And Reserve [Line Items]
Number of corporate executives | Executive		2
Consumer Segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 9,428,000	$ 3,304,000	$ 10,791,000
Consumer Segment | 2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position	92	21	155
Restructuring charges	$ 3,089,000	$ 1,726,000	$ 5,652,000
CPG Segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Number of corporate executives | Executive		3
SPG reportable segment
Restructuring Cost And Reserve [Line Items]
Restructuring charges			$ 0
SPG reportable segment | 2020 MAP to Growth
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 4,633,000	$ 7,585,000
Number of corporate executives | Executive		4
SPG reportable segment | 2020 MAP to Growth | Severance and Benefit Costs
Restructuring Cost And Reserve [Line Items]
Number of positions eliminated | Position	94	130
Restructuring charges	$ 1,592,000	$ 5,338,000