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-Publisher FASB
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Borrowings - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Jun. 15, 2006
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (10,891)	$ (12,470)
Total debt, net	1,130,801	1,178,309
Secured Revolving Credit Facility
Debt Instrument [Line Items]
Secured Revolving Credit Facility	0	0
Junior Subordinated Notes
Debt Instrument [Line Items]
Total debt, net	68,137	66,070
Unamortized discount	32,636	34,703
Senior Notes
Debt Instrument [Line Items]
Senior Unsecured Term Loan (Term Loan)	100,000	150,000
Unamortized debt issuance costs	(10,891)	(12,470)
Total debt, net	1,062,664	1,111,085
Other Secured Notes Payable
Debt Instrument [Line Items]
Total debt, net	0	1,154
6 3/4% Senior Notes Maturing March of 2025 \| Senior Notes
Debt Instrument [Line Items]
Total debt, net	229,555	229,555
5 7/8% Senior Notes Maturing October 2027 \| Senior Notes
Debt Instrument [Line Items]
Total debt, net	394,000	394,000
7 1/4% Senior Notes Maturing October 2029 \| Senior Notes
Debt Instrument [Line Items]
Total debt, net	$ 350,000	$ 350,000
Senior Notes \| 6 3/4% Senior Notes Maturing March of 2025
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)	6.75%
Senior Notes \| 5 7/8% Senior Notes Maturing October 2027
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)	5.88%
Senior Notes \| 7 1/4% Senior Notes Maturing October 2029
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)	7.25%
Junior Subordinated Notes
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)			7.987%