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Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other disclosures
Early termination revenue	$ 6.0	$ 5.1	$ 14.3	$ 24.8
Abandonments	$ 7.0	$ 7.7	$ 22.5	$ 27.2

X

- Definition

Revenue related to early termination of contract.

+ References

No definition available.

+ Details

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X

- Definition

Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

+ Details

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- References

No definition available.

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