Business Combinations - Schedule of Estimated Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Cash		$ 800
Funds held for clients		6,900
Business Acquisitions in 2019 and 2020 [Member]
Business Acquisition [Line Items]
Cash	$ 233	826
Accounts receivable	3,314	1,843
Funds held for clients	1,716	6,878
Operating lease right-of-use asset, net	1,427	2,789
Other assets	250	99
Identifiable intangible assets	4,788	7,725
Operating lease liability - current	(408)	(1,013)
Other current liabilities	(1,856)	(2,245)
Operating lease liability - noncurrent	(1,019)	(1,776)
Client fund obligations	(1,716)	(6,878)
Total identifiable net assets	6,729	8,248
Goodwill	48,584	24,369
Aggregate purchase price	$ 55,313	$ 32,617

Business combination, recognized identifiable assets acquired and liabilities assumed, funds held for clients.

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- Definition

Business combination recognized identifiable assets acquired and liabilities assumed operating lease liability - current.

+ References

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Business combination recognized identifiable assets acquired and liabilities assumed operating lease liability - noncurrent.

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- Definition

Business combination recognized identifiable assets acquired and liabilities assumed operating lease right-of-use asset,net.

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- Definition

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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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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- Definition

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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