Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Business combinations and disposal Business combinations and disposals - Ascend Management Innovations, LLC (Details) - USD ($) $ in Thousands		12 Months Ended
	Feb. 29, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Business combinations
Gain on sale of a business		$ 6,880	$ 0	$ 0
Goodwill		$ 21,453
Ascend Management Innovations LLC
Business combinations
Share capital acquired (as a percent)	100.00%
Purchase consideration, net of cash acquired	$ 44,069
Intangible assets	$ 22,300
Amortization period of intangible assets	18 years
Goodwill	$ 18,554