Other Assets Other Assets (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Other Assets [Abstract]
Property loans receivable	$ 22,230,852atax_PropertyLoanReceivableGross	$ 22,191,515atax_PropertyLoanReceivableGross
Less: Loan loss reserves	(7,098,814)	(7,098,814)
Deferred Finance Costs, Net	4,535,783us-gaap_DeferredFinanceCostsNet	4,659,104us-gaap_DeferredFinanceCostsNet
Fair value of derivative contracts	523,151	267,669
Taxable bonds at fair market value	4,411,214	4,616,565
Bond Purchase Commitment - Fair Market Value Adjustment	5,204,188	5,780,413
Other assets	757,847us-gaap_OtherAssetsMiscellaneous	885,075us-gaap_OtherAssetsMiscellaneous
Total other assets	$ 30,564,221us-gaap_OtherAssets	$ 31,301,527us-gaap_OtherAssets

The change in fair value of a purchase commitment that puts it in an asset position.

No definition available.

Name:	atax_BondPurchaseCommitmentFairMarketValueAdjustmentAsset
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	atax_PropertyLoanReceivableGross
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-Section 45

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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+ Details

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Balance Type:	debit
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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Name Regulation S-X (SX)

-Number 210

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-Publisher FASB

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

+ Details

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- Definition

The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 7

+ Details

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- Details

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- Definition

Amount of other miscellaneous assets.

+ References

No definition available.

+ Details

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