Revenue - Additional Information (Detail) $ in Thousands	3 Months Ended			6 Months Ended
	Nov. 30, 2020 USD ($)	Aug. 31, 2020 USD ($)	Nov. 30, 2019 USD ($)	Nov. 30, 2020 USD ($) Segment	Nov. 30, 2019 USD ($)	May 31, 2020 USD ($)
Disaggregation Of Revenue [Line Items]
Number of reportable segments | Segment				4
Revenue performance obligation description of payment terms				Payment terms and conditions vary by contract type, although our customers’ payment terms generally include a requirement to pay within 30 to 60 days of fulfilling our performance obligations.
Revenue, Practical Expedient, Financing Component [true false]				false
Decrease in net contract assets (liabilities)	$ 11,843			$ 1,117
Net Sales	1,485,915		$ 1,401,292	3,092,586	$ 2,874,056
Long-term deferred revenue	$ 66,900	$ 66,400		$ 66,900		$ 66,000
General Contracting And Roofing Services
Disaggregation Of Revenue [Line Items]
Net Sales		$ 40,400