Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

No definition available.

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- Definition

The estimated maximum percentage of possible loss from the contingency.

+ References

No definition available.

+ Details

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- Definition

Property loan receivable, gross - Amount before allowance of loans held in portfolio. Includes principal only.

+ References

No definition available.

+ Details

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- Definition

Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

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

- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

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Commitments and Contingencies Narrative Tagging (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Property loans receivable	$ 22,230,852atax_PropertyLoanReceivableGross	$ 22,191,515atax_PropertyLoanReceivableGross
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	367,900,000
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			25.00%
Available-For-Sale Securities, Gross Unrealized Loss MTM	17,516	19,582
Villas at Plano Gateway [Member]
Long-term Purchase Commitment, Amount	20,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.00%
15 West Apartments [Member]
Long-term Purchase Commitment, Amount	9,900,000
Debt Instrument, Interest Rate, Stated Percentage	6.25%
Foundation for Affordable Housing [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted				2,800,000
Number of Units in Real Estate Property	96
Property loans receivable	1,542,391	1,560,553		1,603,083
Greens of Pine Glen [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted	1,300,000
Property loans receivable	850,000	850,000
Percentage of Loss Contingency, Range of Possible Loss, Maximum	75.00%
Ohio Properties [Member]
Property loans receivable	2,390,446	2,390,447
Percentage of Loss Contingency, Range of Possible Loss, Maximum	75.00%
Loss Contingency, Range of Possible Loss, Maximum	4,900,000
Silver Moon [Member]
Long-term Purchase Commitment, Amount	8,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Mortgage revenue bonds [Member]
Number of Units in Real Estate Property	7,379
Mortgage revenue bonds [Member] \| Villas at Plano Gateway [Member]
Long-term Purchase Commitment, Amount		20,000,000
Debt Instrument, Interest Rate, Stated Percentage		6.00%
Mortgage revenue bonds [Member] \| 15 West Apartments [Member]
Long-term Purchase Commitment, Amount	$ 9,900,000
Debt Instrument, Interest Rate, Stated Percentage	6.25%