Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	7 Months Ended	12 Months Ended
	Dec. 31, 2015	May. 31, 2015	May. 31, 2014	May. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 5.5	$ 3.8	$ 3.7	$ 3.4
Finite-Lived Intangible Assets, Amortization Expense, 2016	9.0
Finite-Lived Intangible Assets, Amortization Expense, 2017	8.0
Finite-Lived Intangible Assets, Amortization Expense, 2018	8.0
Finite-Lived Intangible Assets, Amortization Expense, 2019	8.0
Finite-Lived Intangible Assets, Amortization Expense, 2020	$ 8.0
Intangible assets, Estimated weighted average useful life	14 years 4 months 24 days
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Estimated weighted average useful life	14 years 8 months 12 days
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Estimated weighted average useful life	5 years
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Estimated weighted average useful life	14 years 4 months 24 days
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Estimated weighted average useful life	10 years
Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Estimated weighted average useful life	10 years 6 months