Aggregate collateral ratio (as defined by the underlying credit agreement)

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- Definition

Debt Instrument, Face Amount, Modification

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No definition available.

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- Definition

Debt Instrument, Interest Rate, Effective Period

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No definition available.

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- Definition

Debt Instrument, Percentage Outstanding after Repurchase with Equity Offerings- Percentage of original amount of debt instrument to remain outstanding after repurchase with equity offerings

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No definition available.

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- Definition

Debt Instrument, Redemption Option with Equity Offerings, Percent of Par

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No definition available.

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- Definition

Debt Instrument, Repurchase Price upon Change of Control, Percent of Par

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No definition available.

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- Definition

Line of Credit Facility, Number of Lenders

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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Period Type:	instant

- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

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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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- Definition

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

+ References

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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-Subparagraph (b)
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Balance Type:	credit
Period Type:	duration

- References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of real estate owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 1A
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Balance Type:	debit
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- References

No definition available.

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- References

No definition available.

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Borrowings - Narrative (Details)	3 Months Ended			6 Months Ended
Borrowings - Narrative (Details)	Mar. 31, 2017 USD ($) lender	Sep. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2017 USD ($) lender	Mar. 31, 2016 USD ($)	Jul. 30, 2016	Jan. 31, 2010 USD ($)
Line of Credit Facility [Abstract]
Amount of available borrowings under the Secured Revolving Credit Facility	$ 140,700,000	$ 106,800,000		$ 140,700,000
Senior Notes [Abstract]
Loss on extinguishment of debt	15,563,000		$ 1,631,000	15,563,000	$ 2,459,000
Secured Debt [Abstract]
Total debt, net	1,334,362,000	1,331,878,000		1,334,362,000
5 3/4% Senior Notes Maturing June 2019
Secured Debt [Abstract]
Total debt, net	321,393,000			321,393,000
Senior Notes
Secured Debt [Abstract]
Total debt, net	$ 1,258,548,000	$ 1,207,526,000		$ 1,258,548,000
Senior Notes \| 6 3/4% Senior Notes Maturing March 2025
Debt Instrument [Line Items]
Debt Instrument, Percentage of Debt Outstanding after Repurchase	35.00%			35.00%
Other Long-term Debt [Abstract]
Stated interest rate on debt instrument (percent)	6.75%	6.75%		6.75%
Junior Subordinated Notes [Abstract]
Stated interest rate on debt instrument (percent)	6.75%	6.75%		6.75%
Aggregate principal amount of debt	$ 250,000,000			$ 250,000,000
Secured Debt [Abstract]
Total debt, net	$ 250,000,000	$ 0		$ 250,000,000
Debt Instrument, Repurchase Price upon Change of Control, Percent of Par	101.00%			101.00%
Senior Notes \| 9 1/8% Senior Notes Maturing May 2019 [Member]
Senior Notes [Abstract]
Call price and make-whole premiums provided for by 2018 Notes			9,800,000
Senior Notes \| 5 3/4% Senior Notes Maturing June 2019
Senior Notes [Abstract]
Call price and make-whole premiums provided for by 2018 Notes			$ 600,000
Other Long-term Debt [Abstract]
Stated interest rate on debt instrument (percent)	5.75%	5.75%		5.75%
Junior Subordinated Notes [Abstract]
Stated interest rate on debt instrument (percent)	5.75%	5.75%		5.75%
Secured Debt [Abstract]
Total debt, net		$ 321,393,000
Term Loan
Senior Notes [Abstract]
Call price and make-whole premiums provided for by 2018 Notes	$ 55,000,000
Other Long-term Debt [Abstract]
Debt instrument term	2 years
Junior Subordinated Notes [Abstract]
Aggregate principal amount of debt	$ 140,000,000			$ 140,000,000
Unamortized accretion	0	800,000		0
Debt Issuance Costs, Net	0	1,451,000		0
Secured Debt [Abstract]
Total debt, net	0	$ 52,669,000		0
Junior Subordinated Notes
Other Long-term Debt [Abstract]
Stated interest rate on debt instrument (percent)						7.987%
Junior Subordinated Notes [Abstract]
Stated interest rate on debt instrument (percent)						7.987%
Effective period of debt instrument interest rate		10 years
Debt Instrument, Face Amount Modification							$ 75,000,000
Unamortized accretion	39,870,000	$ 40,903,000		39,870,000
Secured Debt [Abstract]
Total debt, net	$ 60,903,000	59,870,000		$ 60,903,000
Weighted average fixed interest rate of debt (percent)	4.25%			4.25%
Other secured notes payable
Secured Debt [Abstract]
Total debt, net	$ 14,911,000	11,813,000		$ 14,911,000
Weighted average fixed interest rate of debt (percent)	3.32%			3.32%
Revolving Credit Facility
Line of Credit Facility [Abstract]
Credit facility borrowing capacity	$ 180,000,000	145,000,000		$ 180,000,000
Inventory assets pledged as collateral	$ 800,000,000	1,000,000,000		$ 800,000,000
Number of lenders \| lender	3			3
Borrowings outstanding under facility	$ 0	0		$ 0
Letters of credit secured using cash collateral	$ 39,300,000	$ 38,200,000		$ 39,300,000
Revolving Credit Facility \| Maximum
Line of Credit Facility [Abstract]
Aggregate collateral ratio	4.00	5.00		4.00
Revolving Credit Facility \| Minimum
Line of Credit Facility [Abstract]
Aggregate collateral ratio	1.00	1.00		1.00
Letter of Credit, Cash Secured
Line of Credit Facility [Abstract]
Letters of credit secured using cash collateral	$ 13,100,000	$ 12,100,000		$ 13,100,000
Optional Redemption Under Indenture \| Senior Notes \| 6 3/4% Senior Notes Maturing March 2025
Debt Instrument [Line Items]
Debt Instrument, Percentage of Debt Outstanding after Repurchase	65.00%			65.00%
Debt Instrument, Redemption Option, Percent of Par	106.75%			106.75%