Summary of Significant Accounting Policies - Acquisition-Related Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Accounting Policies [Abstract]
Business Combination, Integration Related Costs	$ 16,067	$ 15,224	$ 6,070
Professional service fees	3,450	12,622	10,876
Acquisition-related adjustments	(3,416)	(106)	220
Total	$ 16,101	$ 27,740	$ 17,166

Adjustments to acquisition-related items that are required to be marked to fair value each reporting period, such as contingent consideration, and other items related to acquisitions for which the measurement period has ended.

No definition available.

+ Details

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- Definition

Costs incurred to effect business combinations which have been expensed during the period. Such costs include the cost of integration-related services provided by third-parties; professional service fees, including direct third party costs related to the acquisition, and legal and other professional service fees associated with disputes and regulatory matters related to acquired entities.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

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