Contractual interest rate for funds borrowed, under the debt agreement.

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(a)(1))

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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

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Credit Facility (Details) (USD $)	Oct. 31, 2012	Apr. 30, 2014 Letter of Credit [Member]	Apr. 30, 2014 Line of Credit [Member]	Apr. 30, 2014 4.0% Convertible Senior Notes due March 15, 2015 [Member]	Apr. 30, 2014 4.0% Convertible Senior Notes due March 15, 2015 [Member] Convertible Notes Payable [Member]
Line of Credit Facility [Line Items]
Credit facility, current borrowing capacity	$ 150,000,000
Interest rate on convertible notes				4.00%	4.00%
Letters of credit collateralized by the credit facility		58,700,000
Borrowings outstanding			$ 0