Fair Value Measurements (Narratives) (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Level 1 Investments
Assets
Unrealized holding gain on investments			$ 500,000
Level 2 Assets and Liabilities
Assets
Transfers of assets between Level 1 and Level 2	$ 0		0
Transfers of liabilities between Level 1 and Level 2	0		0
Long-term debt, fair value	187,600,000		$ 200,000,000
Level 3 Assets and Liabilities
Assets
Transfers of assets between Level 2 and Level 3	0	$ 0
Transfers of liabilities between Level 2 and Level 3	0	0
Intangible asset and goodwill impairment	$ 0	$ 0

Fair value assets Level 2 to Level 3 transfers amount.

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- Definition

Fair value liabilities Level 2 to Level 3 transfers amount.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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- Definition

Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

+ References

No definition available.

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Amount of unrealized holding gain before loss recognized in the income statement for investments in trading securities.

+ References

No definition available.

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