Revenue related to early termination of contract.

No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

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- 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

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- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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- 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.

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Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Basis of Presentation (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Oct. 01, 2017
New accounting pronouncements
Increase in cash provided by operating activities			$ 196,994	$ 150,278
Decrease in net cash used in financing activities			(157,579)	(148,350)
Other disclosures
Early termination revenue	$ 4,000	$ 6,200	8,300	19,700
Abandonments	8,200	18,600	15,500	19,400
Foreign currency (gain) loss	(200)	$ 600	1,400	2,000
ASU 2016-09
New accounting pronouncements
Increase in cash provided by operating activities				3,900
Decrease in net cash used in financing activities				$ 3,900
Cumulative effect adjustment	$ 317		$ 317		$ 300