Revolving Line of Credit - Additional Information (Detail) (USD $)	3 Months Ended
Dec. 31, 2014	Nov. 30, 2014
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	$ 400,000,000	$ 200,000,000
Revolving credit facility, expiration date	Dec. 30, 2019
Revolving credit facility, interest rate description	Interest on amounts borrowed under the credit facility is based on (i) a base rate, which is the greater of (a) the prime rate, (b) the Federal Funds rate plus 0.500% and (c) the one-month LIBOR rate plus 1.000%, plus, in each case, an applicable margin, or (ii) an adjusted LIBOR rate plus an applicable margin. The applicable margin for base rate borrowings ranges from 0% to 0.875% and for LIBOR borrowings ranges from 1.000% to 1.875%, and is determined based on our consolidated leverage ratio
Credit facility restrictive covenant, minimum fixed charge ratio	2.5fico_FixedChargeCoverageRatioMinimum
Credit facility restrictive covenant, maximum consolidated leverage ratio	3.0fico_LeverageRatiosMaximum
Credit facility restrictive covenant, maximum consolidated leverage ratio step up	3.5fico_LeverageRatiosStepUpMaximum
Borrowings outstanding	$ 160,000,000
Interest rate of borrowings outstanding	1.295%us-gaap_DebtWeightedAverageInterestRate
Federal Fund Rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	0.50%
Libor
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	1.00%
Libor \| Minimum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	1.00%
Libor \| Maximum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	1.875%
Base Rate \| Minimum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	0.00%
Base Rate \| Maximum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	0.875%

Fixed Charge Coverage Ratio, Minimum

No definition available.

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- Definition

Leverage Ratios Maximum

+ References

No definition available.

+ Details

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- Definition

Leverage Ratios, Step Up, Maximum

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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- Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Details

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- Details

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- Details

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