Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) (USD $) In Thousands	6 Months Ended
Jul. 31, 2011	Jul. 31, 2010
Cash Flows from Financing Activities
Convertible Senior Notes issuance costs	$ 10,625
Series A preferred stock issuance costs		$ 5,544

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 95-13

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