Pension Plan - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	May 31, 2018	Feb. 28, 2019	Feb. 28, 2018
Defined Benefit Plan Disclosure [Line Items]
Employees covered under noncontributory Pension Plan	20.00%
Compensation period preceding retirement and termination	5 years
Period used for calculating Pension Plan liability	25 years
Cash contribution to the pension plan			$ 3,000,000
Scenario Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum required contribution to the plan is approximately		$ 0
Scenario Forecast [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contribution to the pension plan		2,000,000
Scenario Forecast [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contribution to the pension plan		$ 3,000,000