Number of contiguous tracts of land.

No definition available.

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- Definition

Percentage of limited partnership interest sold.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainLossOnSaleOfProperties
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash received for the sale of real estate that is not part of an investing activity during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	dei_EntityByLocationAxis=atax_NorthernViewMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_EntityByLocationAxis=atax_StPetersburgMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_EntityByLocationAxis=atax_ArboretumMember
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Real Estate Assets Narrative Tagging (Details)	1 Months Ended		3 Months Ended		6 Months Ended
Real Estate Assets Narrative Tagging (Details)	May 31, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 Land
Real Estate [Line Items]
Gain (Loss) on Sale of Properties			$ (16,075)	$ 12,442,929	$ 7,152,512	$ 12,442,929
Douglas County [Member]
Real Estate [Line Items]
Number of contiguous tracts of land to be acquired \| Land							2
Northern View [Member]
Real Estate [Line Items]
Percentage of limited partnership interest sold		99.00%
Proceeds from Sale of Property, Plant, and Equipment		$ 13,800,000
Gain (Loss) on Sale of Properties		$ 7,200,000
St. Petersburg [Member]
Real Estate [Line Items]
Gain (Loss) on Sale of Properties	$ (22,000)
Arboretum [Member]
Real Estate [Line Items]
Proceeds from Sale of Property, Plant, and Equipment						30,200,000
Gain (Loss) on Sale of Properties						$ 12,400,000