Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

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

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-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Debt and Credit Facilities 1.0% Convertible Debentures due 2035 (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 07, 2015	Sep. 30, 2015
Debt Instrument [Line Items]
Long-term debt, face value	$ 2,385,900			$ 2,220,200
Proceeds from Issuance of Long-term Debt	$ 663,757	$ 0
Debt instrument, stated interest rate	2.63515%
Convertible Debentures One Percent Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Long-term debt, face value			$ 676,500
Debt Instrument, Convertible, Carrying Amount of Equity Component			181,100
Deferred Finance Costs, Noncurrent, Net	$ 8,900
Debt instrument, stated interest rate	1.00%
Convertible Debt, Noncurrent			$ 495,400