Real Estate Assets MF Properties (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Land and improvements	$ 15,590,493us-gaap_LandAndLandImprovements	$ 15,589,893us-gaap_LandAndLandImprovements
Buildings and improvements	132,000,442	131,910,221
Carrying Value at September 30, 2012	147,590,935us-gaap_PropertyPlantAndEquipmentGross	147,500,114us-gaap_PropertyPlantAndEquipmentGross
MF Property, Plant and Equipment	120,017,162atax_MfPropertyPlantAndEquipment	119,980,369atax_MfPropertyPlantAndEquipment
Accumulated Depreciation - MF Properties	(15,513,016)	(14,108,154)
Property, Plant and Equipment, Net	104,504,146	105,872,215
Arboretum [Member]
Property, Plant and Equipment [Line Items]
Number of Units	145	145
Land and improvements	1,748,502	1,748,502
Buildings and improvements	19,228,701	19,216,623
Carrying Value at September 30, 2012	20,977,203	20,965,125
Eagle Village [Member]
Property, Plant and Equipment [Line Items]
Number of Units	511	511
Land and improvements	567,880	567,880
Buildings and improvements	12,479,357	12,472,151
Carrying Value at September 30, 2012	13,047,237	13,040,031
Glynn Place [Member]
Property, Plant and Equipment [Line Items]
Number of Units	128	128
Land and improvements	743,996	743,996
Buildings and improvements	4,945,091	4,995,658
Carrying Value at September 30, 2012	5,689,087	5,739,654
Maples on 97th [Member]
Property, Plant and Equipment [Line Items]
Number of Units	258	258
Land and improvements	1,180,058	1,180,058
Buildings and improvements	7,855,899	7,822,681
Carrying Value at September 30, 2012	9,035,957	9,002,739
Meadowview [Member]
Property, Plant and Equipment [Line Items]
Number of Units	230	224
Land and improvements	688,539	688,539
Buildings and improvements	5,482,068	5,479,342
Carrying Value at September 30, 2012	6,170,607	6,167,881
Residences at DeCordova [Member]
Property, Plant and Equipment [Line Items]
Number of Units	110	110
Land and improvements	1,137,832	1,137,832
Buildings and improvements	8,015,812	8,007,390
Carrying Value at September 30, 2012	9,153,644	9,145,222
Residences at Weatherford [Member]
Property, Plant and Equipment [Line Items]
Number of Units	76	76
Land and improvements	1,942,229	1,942,229
Buildings and improvements	5,728,977	5,724,456
Carrying Value at September 30, 2012	7,671,206	7,666,685
The 50/50 Student Housing--UNL [Member]
Property, Plant and Equipment [Line Items]
Number of Units	475	475
Land and improvements	0	0
Buildings and improvements	32,820,776	32,820,776
Carrying Value at September 30, 2012	32,820,776	32,820,776
Woodland Park [Member]
Property, Plant and Equipment [Line Items]
Number of Units	236	236
Land and improvements	1,265,160	1,265,160
Buildings and improvements	14,186,285	14,167,096
Carrying Value at September 30, 2012	$ 15,451,445	$ 15,432,256

Accumulated Depreciation - MF Properties - Accumulated Depreciation for MF Properties

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- Definition

Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

No definition available.

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MF Property, Plant and Equipment - Total of Land, Buildings, Building Improvements, Furniture, Fixtures and Appliances before depreciation used at the MF Properties

+ References

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MF Property Property, Plant and Equipment, Net - The total of the MF Properties Land, Building, Building Improvements, Furniture, Fixtures and Appliances, net of accumulated depreciation

+ References

No definition available.

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- Definition

Amount before accumulated deprecation and depletion of real estate held for productive use and additions or improvements to real estate held for productive use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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