Name:	af_ExtendedPriorPeriodOverWhichLossExperienceFactorsAreEvaluatedToConsiderTrends
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the length of period four, over which the historical loss experience is reviewed.

No definition available.

Name:	af_LengthOfPeriodFourOverWhichHistoricalLossExperienceIsAnalyzed
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the length of period one, over which the historical loss experience is reviewed.

No definition available.

Name:	af_LengthOfPeriodOneOverWhichHistoricalLossExperienceIsAnalyzed
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the length of period three, over which the historical loss experience is reviewed.

No definition available.

Name:	af_LengthOfPeriodThreeOverWhichHistoricalLossExperienceIsAnalyzed
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the length of period two, over which the historical loss experience is reviewed.

No definition available.

Name:	af_LengthOfPeriodTwoOverWhichHistoricalLossExperienceIsAnalyzed
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the minimum length of period, over which the historical loss experience is evaluated for a particular loan type for which the entity may not have sufficient loss history to develop a reasonable estimate of loss.

No definition available.

Name:	af_MinimumLengthOfPeriodOverWhichHistoricalLossExperienceIsAnalyzedForParticularLoanTypeThatMayNotHaveSufficientLossHistory
Namespace Prefix:	af_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Mortgage Loans In Process Of Foreclosure Amount

No definition available.