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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

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-Section 55

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

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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.

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No definition available.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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

-Publisher FASB

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-Subparagraph (SX 210.7-03.16(a))

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Senior Notes - Principal Amounts Carrying Amounts and Fair Values of Senior Notes (Detail) - USD ($)	Sep. 30, 2015	Sep. 30, 2014	Jul. 14, 2010	May. 07, 2008
May 2008 senior notes
Debt Instrument [Line Items]
Principal	$ 131,000,000	$ 202,000,000		$ 275,000,000
Carrying Amounts	131,000,000	202,000,000
Fair Value	144,009,000	214,170,000
July 2010 senior notes
Debt Instrument [Line Items]
Principal	245,000,000	245,000,000	$ 245,000,000
Carrying Amounts	245,000,000	245,000,000
Fair Value	$ 257,563,000	$ 248,557,000