Name:	faf_AvailableForSaleSecuritiesInUnrealizedLossPositionsDefaultRatesAssumption
Namespace Prefix:	faf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item represents the loss severity assumption of the underlying assets in the security that were considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are not other-than-temporarily impaired

No definition available.

Name:	faf_AvailableForSaleSecuritiesInUnrealizedLossPositionsLossSeverityAssumption
Namespace Prefix:	faf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This item represents the rate of prepayment assumption of the underlying assets in the security that were considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are not other-than-temporarily impaired

No definition available.

Name:	faf_AvailableForSaleSecuritiesInUnrealizedLossPositionsPrepaymentSpeedsAssumption
Namespace Prefix:	faf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Expected Cash Flow Collected From Default Rates Weighted Average Percentage Assumption

No definition available.

Name:	faf_ExpectedCashFlowCollectedFromDefaultRatesWeightedAveragePercentageAssumption
Namespace Prefix:	faf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Expected Cash Flow Collected from Loss Severity, Weighted Average Percentage Assumption

No definition available.

Name:	faf_ExpectedCashFlowCollectedFromLossSeverityWeightedAveragePercentageAssumption
Namespace Prefix:	faf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Expected Cash Flow Collected From Prepayment Speeds Weighted Average Percentage Assumption

No definition available.