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

No definition available.

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Data Type:	num:percentItemType
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ 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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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Financing Arrangements - Senior Unsecured Notes (Details) - Senior unsecured notes - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2019	Feb. 02, 2016	Jul. 17, 2015	Mar. 31, 2013
Senior Unsecured Notes Issued March 2013 and Due March 2025
Financial arrangement
Principal amount of debt instrument				$ 100.0
Interest rate (as a percent)				3.35%
Coupon rate increase based on leverage ratio (as a percent)	0.50%
Senior Unsecured Notes Issued July 2015 and Due March 2025
Financial arrangement
Principal amount of debt instrument			$ 25.0
Interest rate (as a percent)			3.70%
Senior Unsecured Notes Issued February 2016 and Due March 2026
Financial arrangement
Principal amount of debt instrument		$ 75.0
Interest rate (as a percent)		3.93%