Share Based Compensation Arrangement By Share Based Payment Award Employee Stock Purchase Plan Offering Term

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Offering Period

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- Definition

Share Based Compensation Arrangement By Share-based Payment Award, Options, Outstanding, Number, With Exercise Prices Lower Than Market Price

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Payout

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Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Period

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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- Definition

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

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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- Definition

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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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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Stock-Based Employee Benefit Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP, purchase price of the stock as a percentage of fair market value on the exercise date	15.00%
Share-based compensation expense	$ 115.4	$ 112.5	$ 93.7
Tax benefit related to share-based compensation expense	13.5	$ 14.0	$ 13.2
Unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 144.0
Unrecognized compensation cost, weighted average recognition period	2 years 2 months 19 days
Cash received from stock option exercises	$ 3.2
Tax benefit from the stock option exercises	$ 3.4
Weighted average fair value of options granted (in dollars per share)	$ 134.91	$ 139.11	$ 99.30
Number of options that had exercise prices lower than the market price of common stock (in shares)	180,000
Market price of common stock (in dollars per share)	$ 412.01
Total intrinsic value of options exercised	$ 14.5	$ 15.8	$ 132.6
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards vesting period	4 years
Restricted Stock Units Subject To Market or Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards vesting period	3 years
Restricted stock units and non-vested shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of restricted stock units, performance stock units, and market stock units (in dollars per share)	$ 416.62	$ 505.70	$ 356.66
Total intrinsic value of restricted stock units, performance stock units, and market stock units	$ 97.3	$ 156.6	$ 159.0
Performance stock units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of restricted stock units, performance stock units, and market stock units (in dollars per share)	$ 407.49	$ 506.91	$ 354.18
Total intrinsic value of restricted stock units, performance stock units, and market stock units	$ 25.9	$ 34.7	$ 36.5
Market stock units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of restricted stock units, performance stock units, and market stock units (in dollars per share)	$ 493.66	$ 471.16	$ 249.13
Total intrinsic value of restricted stock units, performance stock units, and market stock units	$ 7.8	$ 34.5	$ 44.6
Market stock units (MSUs) \| Performance period year one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	1 year
Market stock units (MSUs) \| Performance period year two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	2 years
Market stock units (MSUs) \| Performance period year three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	3 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards vesting period	3 years
Minimum \| Performance stock units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance condition payout (percent)	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards vesting period	4 years
Maximum \| Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards term	10 years
Maximum \| Performance stock units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance condition payout (percent)	200.00%
2012 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grants under stock plan (in shares)	5,270,822
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grants under stock plan (in shares)	874,772
Authorized shares of common stock for grant under stock plan (in shares)	1,000,000
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%
Employee stock purchase plans, offering period (in months)	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Offering Period	6 months
Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares of common stock for grant under stock plan (in shares)	5,900,000