Maximum excess availability level at which financial maintenance covenants would apply.

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Maximum excess availability level at which financial maintenance covenants would apply, as a percentage of aggregate commitments.

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No definition available.

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Total other amounts reducing excess availability.

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Potential increase in the size of credit facility.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Amount of the required periodic payments applied to principal.

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Amount, after accumulated amortization, of debt discount.

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Amount of write-off of debt issuance costs and debt discounts related to prepetition debt obligations.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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No definition available.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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No definition available.

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

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Date the credit facility terminates, in CCYY-MM-DD format.

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The effective interest rate at the end of the reporting period.

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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.

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

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash outflow for loan and debt issuance costs.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended			84 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Nov. 25, 2021
Agreement termination date	Jul. 13, 2021
Loss on early extinguishment of debt	$ 0	$ 0	$ 31,300
Gain (Loss) on Repurchase of Debt Instrument			25,200
Write off of Deferred Debt Issuance Cost			4,400
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts			1,700
Future maturities of outstanding borrowings
CY plus 1	5,600
CY plus 2	5,400
CY plus 3	5,300
CY plus 4	5,000
CY plus 5	466,700
Payments of Financing Costs	1,000	$ 1,200	$ 8,500
Revolving Credit Facility [Member]
Revolving credit facility amount	225,000
Potential increase size of the credit facility by an additional amount	$ 150,000
Line of Credit Facility, Interest Rate at Period End	12500.00%
Aggregate commitments availability	$ 17,500
Aggregate commitments availability, percentage	10.00%
Outstanding letter of credit accrued fees and expenses	$ 23,600
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses	$ 113,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	2500.00%
Swing Line Loans [Member]
Revolving credit facility amount	$ 25,000
Letter Of Credit [Member]
Revolving credit facility amount	60,000
Secured Debt [Member]
Deferred Finance Costs, Noncurrent, Gross	$ 8,500
Borrowing rate in addition to LIBOR	25000.00%
Debt Instrument, Interest Rate, Effective Percentage	4.56%
Debt Instrument, Periodic Payment, Principal	$ 1,225
Long-term Debt, Gross	500,000
Future maturities of outstanding borrowings
Debt Instrument, Unamortized Discount	1,500
Financial Liabilities Fair Value Disclosure	$ 490,900
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Revolving Credit Facility [Member]
Borrowing rate in addition to LIBOR	12500.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Secured Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage	0.75%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Borrowing rate in addition to LIBOR	15000.00%
Base Rate [Member] \| Minimum [Member] \| Revolving Credit Facility [Member]
Borrowing rate in addition to LIBOR	2500.00%
Base Rate [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Borrowing rate in addition to LIBOR	5000.00%
Scenario, Forecast [Member] \| Secured Debt [Member]
Agreement termination date				Nov. 25, 2021