Goodwill and Intangible Assets - Changes in Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Goodwill [Roll Forward]
Goodwill, beginning	$ 83,954	$ 58,517
Goodwill attributable to acquisitions	84,330	25,437
Goodwill, ending	168,284	83,954
Merchant Services
Goodwill [Roll Forward]
Goodwill, beginning	69,666	49,173
Goodwill attributable to acquisitions	38,806	20,493
Goodwill, ending	108,472	69,666
Accumulated impairment losses			$ 11,458
Proprietary Software and Payments
Goodwill [Roll Forward]
Goodwill, beginning	14,288	9,344
Goodwill attributable to acquisitions	45,524	4,944
Goodwill, ending	59,812	14,288
Accumulated impairment losses			0
Other
Goodwill [Roll Forward]
Goodwill, beginning	0	0
Goodwill attributable to acquisitions	0	0
Goodwill, ending	$ 0	$ 0
Accumulated impairment losses			$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

+ References

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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