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

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-Section S99
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Amount, after accumulated amortization, of debt discount (premium).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Borrowings - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Sep. 30, 2017	Jul. 30, 2016
Debt Instrument [Line Items]
Unamortized debt premium, net	$ (3,027)	$ (3,413)
Unamortized debt issuance costs	(15,905)	(14,800)
Total debt, net	1,325,457	1,327,412
Senior Notes
Debt Instrument [Line Items]
Unamortized debt premium, net	(3,026)	(3,413)
Unamortized debt issuance costs	(15,905)	(14,800)
Total debt, net	$ 1,258,348	1,259,840
Senior Notes \| 5 3/4% Senior Notes Maturing June 2019
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	5.75%
Total debt, net	$ 96,393	$ 321,393
Senior Notes \| 7 1/2% Senior Notes Maturing September 2021
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	7.50%	7.50%
Senior Notes \| 8 3/4% Senior Notes Maturing March 2022
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	8.75%	8.75%
Total debt, net	$ 500,000	$ 500,000
Senior Notes \| 7 1/4% Senior Notes Maturing February 2023
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	7.25%	7.25%
Total debt, net	$ 24,834	$ 199,834
Senior Notes \| 6 3/4% Senior Notes Maturing March of 2025
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	6.75%	6.75%
Total debt, net	$ 250,000	$ 250,000
Senior Notes \| 5 7/8% Senior Notes Maturing October 2027
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	5.875%	0.00%
Total debt, net	$ 400,000	$ 0
Junior Subordinated Notes
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)			7.987%
Total debt, net	62,970	61,937
Other Secured Notes payable
Debt Instrument [Line Items]
Total debt, net	$ 4,139	$ 5,635