Stock-Based Employee Benefit Plans - Additional Information (Details) shares in Thousands	3 Months Ended
Dec. 31, 2022 shares
Employee stock option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards term	10 years
Restricted stock units not subject to market or performance conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Restricted stock units subject to market or performance conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares of common stock for grant under stock plan (in shares)	1,000
ESPP, percentage of salary withheld through payroll deductions to purchase FICO common stock	15.00%
ESPP, purchase price of the stock as a percentage of fair market value on the exercise date	85.00%
Shares Issued during the period	0

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
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Discount rate from fair value on purchase date that participants pay for shares.

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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

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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