Retirement and Postretirement Benefits Plans - Components of Net Periodic Benefit Cost and Changes Recognized Other Comprehensive Income, Defined Benefit Pension Plan (Detail) (Defined Benefit Pension Plans [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2013
Defined Benefit Pension Plans [Member]
Components of net periodic benefit cost:
Service cost	$ 683	$ 1,115	$ 1,369
Interest cost	7,249	7,065	7,394
Expected return on plan assets	(6,522)	(6,267)	(6,473)
Amortization of transition obligation	5	6	7
Amortization of prior service cost	580	190	240
Amortization of actuarial loss	2,827	3,485	3,514
Recognition of prior service cost upon curtailment		1,746
Defined benefit plan, net periodic benefit cost, total	4,822	7,340	6,051
Other changes in plan assets and benefit obligations recognized in other comprehensive income:
Actuarial loss	8,610	941	5,657
Prior service cost	580	414	231
Amortization of prior service cost	(580)	(190)	(240)
Amortization of actuarial loss	(2,827)	(3,485)	(3,514)
Amortization of transition obligation	(5)	(6)	(7)
Change in control		2,613
Curtailment gain		(7,164)
Recognition of prior service cost upon curtailment		(1,746)
Total recognized in other comprehensive income	5,778	(8,623)	2,127
Total recognized in net periodic benefit cost and other comprehensive income	$ 10,600	$ (1,283)	$ 8,178