Other Assets Other Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Property loan receivable, gross	$ 22,191,515atax_PropertyLoanReceivableGross	$ 21,549,927atax_PropertyLoanReceivableGross
Loans and Leases Receivable, Allowance	7,098,814	7,023,814
Deferred Finance Costs, Net	4,659,104us-gaap_DeferredFinanceCostsNet	2,503,679us-gaap_DeferredFinanceCostsNet
Interest Rate Derivatives, at Fair Value, Net	267,669	888,120
Available-for-sale Securities, Debt Securities	4,616,565	4,075,953
Inventory, Land Held-for-sale	0us-gaap_InventoryLandHeldForSale	1,465,000us-gaap_InventoryLandHeldForSale
Bond Purchase Commitment - Fair Market Value Adjustment - Liability	5,780,413	0
Other Assets, Miscellaneous	885,075us-gaap_OtherAssetsMiscellaneous	899,426us-gaap_OtherAssetsMiscellaneous
Other Assets	$ 31,301,527us-gaap_OtherAssets	$ 24,358,291us-gaap_OtherAssets

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

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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

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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- 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

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-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

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- 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

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-Name Accounting Standards Codification

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- Definition

Carrying amount as of the balance sheet date of parcels of land held for sale, and on which the entity has no intention or no further intention to perform construction activities.

+ References

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

-Publisher FASB

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-Topic 210

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-Subparagraph (SX 210.5-02.6(a))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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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

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-Paragraph 11B

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-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

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Regulation S-X (SX)

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- Definition

Amount of other miscellaneous assets.

+ References

No definition available.

+ Details

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