The percentage of ownership of available-for-sale securities.

No definition available.

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

- Definition

Number of Installments of Contributed Capital

+ References

No definition available.

+ Details

Name:	atax_NumberOfInstallmentsOfContributedCapital
Namespace Prefix:	atax_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of owners of the consolidated VIE's.

+ References

No definition available.

+ Details

Name:	atax_NumberOfOwners
Namespace Prefix:	atax_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of Partners of a Company.

+ References

No definition available.

+ Details

Name:	atax_NumberOfPartners
Namespace Prefix:	atax_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of variable interest entities owned.

+ References

No definition available.

+ Details

Name:	atax_NumberOfVariableInterestEntities
Namespace Prefix:	atax_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Total contributions made by each class of partners (i.e., general, limited and preferred partners).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

+ Details

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

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=SL6759159-111685

+ Details

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Variable Interest Entities Narrative Tagging (Details) (USD $)	6 Months Ended						6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended
	Jun. 30, 2014	Dec. 31, 2013 properties	Jun. 30, 2014 Total Owners [Member] owners	Jun. 30, 2014 Related party owner [Member] owners	Jun. 30, 2014 Consolidated VIEs [Member] properties	Jun. 30, 2014 Unconsolidated Properties [Member] properties	Jun. 30, 2014 Ashley Square [Member]	Mar. 31, 2010 Cross Creek [Member] installments	Jun. 30, 2014 Cross Creek [Member] limited	Mar. 31, 2010 First Installment [Member] Cross Creek [Member]
Available-for-Sale Securities, Ownership Percentage	100.00%						100.00%		100.00%
Number of Owners			4	2
Number of Variable Interest Entities		4			2	2
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage							99.00%		99.00%
Number of Partners									3
Partners' Capital Account, Contributions								$ 2,200,000		$ 563,000
Number of Installments of Contributed Capital								3
Noncontrolling Interest, Ownership Percentage by Parent									1.00%