| Variable Interest Entity (Tables) | 12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Sep. 30, 2021 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Variable Interest Entity, Measure of Activity [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Purchase Price Allocation of Purchase of Acquired Identifiable Assets, Liabilities Assumed and Goodwill | The table below outlines the purchase price allocation of the purchase for SW Financial to the acquired identifiable assets, liabilities assumed and goodwill: 
 
 
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| Summary of Assets Acquired and Liabilities Assumed Within Fair Value Hierarchy | The assets acquired and liabilities assumed were classified within the fair value hierarchy table below in accordance with our fair value measurements policy (see Note 2). 
 
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