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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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Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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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.

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Borrowings - Schedule of Long-term Debt (Details) - USD ($)	Dec. 31, 2020	Sep. 30, 2020	Jul. 30, 2016
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (10,483,000)	$ (10,891,000)
Total outstanding borrowings of unconsolidated entities	1,131,725,000	1,130,801,000
Senior Notes
Debt Instrument [Line Items]
Senior Unsecured Term Loan (Term Loan)	100,000,000	100,000,000
Unamortized debt issuance costs	(10,483,000)	(10,891,000)
Total outstanding borrowings of unconsolidated entities	1,063,072,000	1,062,664,000
Senior Notes \| 6 3/4% Senior Notes Maturing March of 2025
Debt Instrument [Line Items]
Total outstanding borrowings of unconsolidated entities	229,555,000	229,555,000
Senior Notes \| 5 7/8% Senior Notes Maturing October 2027
Debt Instrument [Line Items]
Total outstanding borrowings of unconsolidated entities	394,000,000	394,000,000
Senior Notes \| 7 1/4% Senior Notes Maturing October 2029
Debt Instrument [Line Items]
Total outstanding borrowings of unconsolidated entities	350,000,000	350,000,000
Junior Subordinated Notes
Debt Instrument [Line Items]
Total outstanding borrowings of unconsolidated entities	68,653,000	68,137,000
Stated interest rate on debt instrument			7.987%
Unamortized accretion	32,120,000	32,636,000
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving Credit Facility	$ 0	$ 0
Senior Notes \| 6 3/4% Senior Notes Maturing March of 2025
Debt Instrument [Line Items]
Stated interest rate on debt instrument	6.75%
Senior Notes \| 5 7/8% Senior Notes Maturing October 2027
Debt Instrument [Line Items]
Stated interest rate on debt instrument	5.88%
Senior Notes \| 7 1/4% Senior Notes Maturing October 2029
Debt Instrument [Line Items]
Stated interest rate on debt instrument	7.25%