Transactions with Related Parties Transactions with Related Parties Narrative (Details)	3 Months Ended
Mar. 31, 2016 USD ($) Property	Mar. 31, 2015 USD ($)
Rate for administration fees	0.45%
Fees and commissions, other	$ 388,000	$ 534,000
Management fees revenue	312,000	324,000
Placement advisory fees	$ 194,000	267,000
MF Properties Managed [Member]
Number of Real Estate Properties \| Property	7
Majority-Owned Subsidiary, Unconsolidated [Member]
Payment for administrative fees	$ 687,000	620,000
Affiliated Entity [Member]
Payment for administrative fees	$ 0	$ 16,500

Consulting fees related to the placement and continued performance monitoring of mortgage revenue bond purchases.

No definition available.

Name:	atax_PlacementAdvisoryFees
Namespace Prefix:	atax_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Rate for administration fees - rate charged on the bonds and loans collateralized by the underlying properties for administration of the assets

+ References

No definition available.

+ Details

Name:	atax_RateForAdministrationFees
Namespace Prefix:	atax_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fee and commission revenue earned from sources not otherwise specified in the existing taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

Name:	us-gaap_FeesAndCommissionsOther
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue, comprised of base and incentive revenue derived from the management of joint ventures, managing third-party properties, or another entity's operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount paid to managing member or general partner, affiliate of managing member or general partner, or affiliate of limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_RealEstatePropertiesAxis=atax_RealEstatePropertiesManagedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_MajorityOwnedSubsidiaryUnconsolidatedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
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Period Type: