Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Debt - Composition of Long Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Oct. 31, 2016	Sep. 30, 2016
Debt Instrument
Total long-term debt	$ 755,000		$ 675,000
Less: unamortized debt issuance costs	(3,899)		(3,559)
Less: current maturities	(39,996)		(19,986)
Total long-term debt due after one year	$ 711,105		651,455
Senior Notes \| 4.12%, due September 2046
Debt Instrument
Interest rate	4.12%
Total long-term debt	$ 200,000		200,000
Senior Notes \| 4.98%, due March 2044
Debt Instrument
Interest rate	4.98%
Total long-term debt	$ 175,000		175,000
Senior Notes \| 4.12%, due October 2046
Debt Instrument
Interest rate	4.12%	4.12%
Total long-term debt	$ 100,000		0
Senior Notes \| 6.21%, due September 2036
Debt Instrument
Interest rate	6.21%
Total long-term debt	$ 100,000		100,000
Senior Notes \| 2.95%, due June 2026
Debt Instrument
Interest rate	2.95%
Total long-term debt	$ 100,000		$ 100,000
Medium-Term Notes \| 6.17%, due June 2017
Debt Instrument
Interest rate			6.17%
Total long-term debt	$ 0		$ 20,000
Medium-Term Notes \| 7.25%, due November 2017
Debt Instrument
Interest rate	7.25%
Total long-term debt	$ 20,000		20,000
Medium-Term Notes \| 5.67%, due January 2018
Debt Instrument
Interest rate	5.67%
Total long-term debt	$ 20,000		20,000
Medium-Term Notes \| 6.50%, due August 2033
Debt Instrument
Interest rate	6.50%
Total long-term debt	$ 20,000		20,000
Medium-Term Notes \| 6.13%, due October 2034
Debt Instrument
Interest rate	6.13%
Total long-term debt	$ 20,000		$ 20,000