Pension and Profit Sharing Plans - Additional information (Detail) (USD $)	12 Months Ended
	Mar. 31, 2015 CompensationPlan Employee	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Amendment of pension plan service cost	$ 805,000
Amendment in pension plan	We amended one of our pension plans during March 2015, which increased our prior service cost by approximately $0.8 million. This amount is included in other comprehensive income and will be recognized in our statement of earnings as pension expense over the next three fiscal years.
Current actuarial estimates contributions	200,000	200,000	100,000
Costs relating to employer discretionary contributions	5,300,000	4,500,000	3,300,000
Number of employees covered under multi-employer pension plans	60
Number of multi-employer plans	5
Collective bargaining agreement for employer covered under multi-employer plans, Expiration beginning date	Jun. 30, 2015
Collective bargaining agreement for employer covered under multi-employer plans, Expiration ending date	Mar. 31, 2017
Expenses related to Multi employer plans	1,000,000	1,000,000	200,000
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Expenses related to Multi employer plans				1,000,000
Salaried Employees [Member]
Defined Benefit Plan Disclosure [Line Items]
Employees fully vesting in employer's contributions made beginning in 2007, requirement years	6 years
Hourly Employees [Member]
Defined Benefit Plan Disclosure [Line Items]
Employees fully vesting in employer's contributions made beginning in 2007, requirement years	3 years
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Current actuarial estimates contributions	500,000
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Current actuarial estimates contributions	$ 1,000,000