Benefit Plans (Narrative) (Details)	12 Months Ended
	Feb. 29, 2016 USD ($) defined_benefit_plan	Feb. 28, 2015 USD ($)	Feb. 28, 2014 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of frozen noncontributory plans | defined_benefit_plan	2
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated future amortization of actuarial losses	$ 1,500,000
Expected contributions to the pension plan next year	0
Benefit payments next twelve months		$ 3,000,000
Benefit payments year two		3,000,000
Benefit payments year three		4,000,000
Benefit payments year four		4,000,000
Benefit payments year five		4,000,000
Restoration Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated future amortization of actuarial losses	0
Expected contributions to the pension plan next year	500,000
Expected contributions to the pension plan year two	500,000
Expected contributions to the pension plan year three	500,000
Expected contributions to the pension plan year four	500,000
Expected contributions to the pension plan year five	500,000
Retirement Savings Plan401k
Defined Benefit Plan Disclosure [Line Items]
Total cost for company contributions	$ 29,800,000	$ 27,900,000	$ 25,000,000
Equity securities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets target allocation	75.00%
Fixed income securities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets target allocation	25.00%