Retirement and Postretirement Benefit Plans - Summary of Fair Value of Defined Benefit Pension Plan Assets, Postretirement Benefit Plans (Detail) (Postretirement Benefits Plans [Member], USD $) In Thousands, unless otherwise specified	Feb. 28, 2014	Feb. 28, 2013	Feb. 29, 2012
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	$ 48,757	$ 51,794	$ 57,563
Short-term investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	1,312	1,706
Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	12,968	14,195
Fixed-income funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	34,477	35,893
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	12,968	14,195
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Short-term investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	12,968	14,195
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fixed-income funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets
Significant other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	35,789	37,599
Significant other observable inputs (Level 2) [Member] | Short-term investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	1,312	1,706
Significant other observable inputs (Level 2) [Member] | Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets
Significant other observable inputs (Level 2) [Member] | Fixed-income funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of defined benefit pension plan assets	$ 34,477	$ 35,893