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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense related to intangible assets	$ 11,630	$ 8,850	$ 6,744
Estimated intangible asset amortization for 2017	15,000
Estimated intangible asset amortization for 2018	15,000
Estimated intangible asset amortization for 2019	15,000
Estimated intangible asset amortization for 2020	15,000
Estimated intangible asset amortization for 2021	$ 15,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Expected remaining useful life	20 years
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Expected remaining useful life	17 years
Capitalized Software [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected remaining useful life	7 years
Capitalized Software [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected remaining useful life	3 years