Letter of credit maximum limit allowable for issue.

No definition available.

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- Definition

Mandatory redemption of bonds annual amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Mandatory redemption of bonds annual start date.

+ References

No definition available.

+ Details

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- Definition

Maturity period of senior note.

+ References

No definition available.

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- Definition

Property and equipment with undepreciated cost pledge as collateral for long term debt.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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))
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

+ Details

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Period Type:	duration

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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.

+ References

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Period Type:	instant

- 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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Balance Type:	credit
Period Type:	instant

- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)(a)
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- Details

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Long-Term Debt (Narrative) (Details) - USD ($)		9 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 19, 2017	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2013	Dec. 31, 2010
Debt Instrument [Line Items]
Maximum amount of unused letters of credit allowed to issue		$ 30,000,000
Unused letters of credit issued		9,600,000
Property and equipment with undepreciated cost pledge as collateral for long term debt		217,000,000
Excess net worth calculated under covenants in the Notes, the Bonds, and the Line		$ 96,800,000
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative notional amount	$ 58,500,000
Derivative, fixed interest rate	3.92%
Interest Rate Swap [Member] \| One-Month LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate	1.65%
Senior Notes, Interest Rate of 5.75%, Maturing 2023 [Member]
Debt Instrument [Line Items]
Debt instrument principal amount				$ 700,000,000
Maturity period of senior notes		2023
Debt instrument stated interest rate				5.75%
Redemption period of senior notes description		redeem all or a portion of the Notes at any time on or after June 15, 2018
Secured Debt [Member]
Debt Instrument [Line Items]
Debt instrument principal amount			$ 60,000,000
Debt maturity date		Oct. 01, 2027
Monthly principal amortization		$ 500,000
Recovery Zone Facility Bonds [Member]
Debt Instrument [Line Items]
Debt maturity date		Jan. 01, 2036
Description of interest rate on bonds		The interest rate on the Bonds is equal to one month LIBOR (adjusted monthly) plus a credit spread, adjusted to reflect the income tax exemption.
Total amount of bonds funded					$ 99,700,000
Annual amount of redemption of bonds		$ 4,500,000
Mandatory bonds redemption beginning period		Jan. 01, 2014
Credit Line [Member]
Debt Instrument [Line Items]
Debt maturity date		Sep. 30, 2022
Line of credit facility		$ 175,000,000
Borrowings outstanding		$ 20,100,000