Debt (Details) (USD $) In Thousands, unless otherwise specified	Feb. 29, 2012	Feb. 28, 2011
Long-term debt and net of unamortized discounts
LONG-TERM DEBT	$ 225,181	$ 232,688
7.375% senior notes, due 2021 [Member]
Long-term debt and net of unamortized discounts
LONG-TERM DEBT	225,000
7.375% senior notes, due 2016 [Member]
Long-term debt and net of unamortized discounts
LONG-TERM DEBT		213,077
7.375% notes, due 2016 [Member]
Long-term debt and net of unamortized discounts
LONG-TERM DEBT		19,430
6.10% senior notes, due 2028 [Member]
Long-term debt and net of unamortized discounts
LONG-TERM DEBT	$ 181	$ 181

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant