Borrowings - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Sep. 30, 2016
Debt Instrument [Line Items]
Unamortized debt premium, net	$ (1,535)	$ (1,482)
Debt issuance costs	14,509	15,514
Total debt, net	1,336,483	1,331,878
Senior Notes
Debt Instrument [Line Items]
Unamortized debt premium, net	(2,260)	(2,362)
Debt issuance costs	13,314	14,063
Total debt, net	$ 1,208,173	$ 1,207,526
Senior Notes \| 5 3/4% Senior Notes Maturing June 2019
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	5.75%	5.75%
Total debt, net	$ 321,393	$ 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%
Total debt, net	$ 198,000	$ 198,000
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	$ 199,834	$ 199,834
Term Loan
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	6.75%
Total debt, net	$ 53,080	52,669
Junior Subordinated Notes
Debt Instrument [Line Items]
Stated interest rate on debt instrument (percent)	7.987%
Total debt, net	$ 60,387	59,870
Other Secured Notes payable
Debt Instrument [Line Items]
Total debt, net	$ 14,843	$ 11,813

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28567-108399

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+ References

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