Related Party Transactions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Related Party Transaction [Line Items]
Investment in convertible preferred stock in a private company	$ 10

Carrying amount as of the balance sheet date of investments in all related parties.

No definition available.

Name:	fico_InvestmentsInRelatedParties
Namespace Prefix:	fico_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant