Benefit Plans - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
Jul. 31, 2018	Apr. 05, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units, granted, shares	2,400,000
Share-based compensation arrangement by share-based payment award, non-option equity instruments, outstanding, number	4,400,000
Stock Issued During Period, Shares, Issued for Services	158,708
Noninterest Expense Directors Fees	$ 0.3
Maximum [Member] \| Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance		500,000
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units, general vesting period	3 years
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units, general vesting period	4 years
2018 Omnibus Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance		4,000,000

Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Net number of non-option equity instruments granted to participants.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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