The number of variable interest entities owned.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The aggregate revenue from building and real estate development, which may include improvements (such as drainage, utilities, grading and subdividing) to a parcel of land, and general contracting services during the reporting period.

+ 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(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Definition

The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- 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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Article 9

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- 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

+ Details

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- 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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Data Type:	xbrli:monetaryItemType
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- Details

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Period Type:

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=atax_TEBSIIFacilityMember
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- Details

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- Details

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Transactions with Related Parties Transactions with Related Parties Narrative (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 entities properties	Dec. 31, 2013 properties	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2013 properties
rate for administration fees	0.45%atax_RateForAdministrationFees
Fees and Commissions, Other	$ 1,700,000us-gaap_FeesAndCommissionsOther	$ 1,200,000us-gaap_FeesAndCommissionsOther	$ 1,400,000us-gaap_FeesAndCommissionsOther
Construction Revenue		672,000us-gaap_ConstructionRevenue
Management Fees Revenue	1,300,000us-gaap_ManagementFeesRevenue	1,200,000us-gaap_ManagementFeesRevenue	1,200,000us-gaap_ManagementFeesRevenue
Placement Advisory Fees	1,400,000atax_PlacementAdvisoryFees	752,000atax_PlacementAdvisoryFees
Number of Variable Interest Entities	11atax_NumberOfVariableInterestEntities	6atax_NumberOfVariableInterestEntities
Majority-Owned Subsidiary, Unconsolidated [Member]
Payment for Administrative Fees	2,000,000	1,500,000	948,000
Affiliated Entity [Member]
Payment for Administrative Fees	138,000	144,000	133,000
Eagle Ridge [Member] \| Affiliated Entity [Member]
Payment for Administrative Fees			71,000
Trust Portfolio--PHCFT [Member]
Debt Instrument, Unamortized Premium				653,000
Available-for-sale Securities [Member] \| Arbors at Hickory Ridge [Member]
Debt Instrument, Unamortized Premium					100,000
Trust Portfolio--MBS Bonds [Member]
Debt Instrument, Unamortized Premium			316,000
Variable Interest Entity, Primary Beneficiary [Member]
Number of Variable Interest Entities	2
Total Owners [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Number of Variable Interest Entities						2
TEBS II Facility [Member]
Placement Advisory Fees	$ 300,000