Goodwill and Intangible Assets Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Finite-Lived Intangible Assets [Line Items]
Balance as of September 30, 2018	$ 450,001
Acquisitions		$ 60,800
Amortization	(78,126)
Effect of foreign currency translation	(429)
Balance at June 30, 2019	372,934
Other Acquisitions [Member]
Finite-Lived Intangible Assets [Line Items]
Acquisitions	$ 1,488

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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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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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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