Adverse change rate - effective rate if 10% adverse change in market occurs

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. This does not include premiums.

+ References

No definition available.

+ Details

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- Definition

Effective rate - the effective rate for the available for sale securities held in the portfolio

+ References

No definition available.

+ Details

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- Definition

Number of Available for Sale Securities, Mortgage Backed Securities

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading at the time of a sale. This does not include premiums.

+ References

No definition available.

+ Details

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- Definition

TOB Financing - Tender Option Bond Financing Facility

+ References

No definition available.

+ Details

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- Definition

The percentage of difference of the valuation of an asset between the Company and a third party.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

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- Definition

The cash outflow for the purchase of securities issued by a governmental agency or corporation (for example, GNMA or FHLMC) or by private issuers (for example, banks and mortgage banking enterprises) secured by and repaid from underlying mortgages, which were designated as available for sale when acquired.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3521-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 26

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3574-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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Balance Type:	credit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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MBS Investments Narrative Tagging (Details) (USD $)	3 Months Ended	12 Months Ended			3 Months Ended
MBS Investments Narrative Tagging (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014 Integer	Mar. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Tolerable Range of Difference in Valuation		0.00%			0.00%
Payments to Acquire Mortgage Backed Securities (MBS) categorized as Available-for-sale	$ 3,800,000	$ 0	$ 12,629,888	$ 37,573,386
Adverse change rate		10.00%atax_AdverseChangeRate			10.00%atax_AdverseChangeRate
Available-for-sale Securities, Gross Unrealized Losses		(19,582)	2,434,964
Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		4.70%			4.70%
Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		8.30%			8.30%
Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of Available for Sale Securities, Mortgage Backed Securities		6			6
Available for Sale Securities, not Including Premiums	3,700,000	14,765,000	42,830,000	31,620,000	14,765,000
Payments to Acquire Mortgage Backed Securities (MBS) categorized as Available-for-sale					24,600,000
Sale of Available for Sale Securities, not Including Premiums		24,400,000			24,400,000
Adverse change rate		10.00%			10.00%
Available-for-sale Securities, Gross Unrealized Losses		(526,083)	(5,956,155)
Trust Portfolio--MBS Bonds [Member] \| Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		3.70%			3.70%
Trust Portfolio--MBS Bonds [Member] \| Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		5.20%			5.20%
LIFERS [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for Sale Securities, not Including Premiums		9,200,000			9,200,000
TOB Financing				6,500,000
SPEARS [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing		34,900,000			34,900,000
10% adverse [Member] \| Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		5.10%			5.10%
10% adverse [Member] \| Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		9.10%			9.10%
10% adverse [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses		800,000
10% adverse [Member] \| Trust Portfolio--MBS Bonds [Member] \| Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		4.10%			4.10%
10% adverse [Member] \| Trust Portfolio--MBS Bonds [Member] \| Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate		5.80%			5.80%
Mortgage Backed Security Trust 4 [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing		6,000,000			6,000,000
Mortgage Backed Security Trust 5 [Member] [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing		5,300,000			5,300,000	2,500,000
Mortgage Backed Security Trust 5 [Member] [Member] \| LIFERS [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing						540,000
Mortgage Backed Security Trust 5 [Member] [Member] \| SPEARS [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing						2,000,000
Mortgage Backed Security Trust 6 [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing		7,800,000			7,800,000
Mortgage Backed Security Trusts 4, 5, 6 [Member] \| Trust Portfolio--MBS Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing		$ 19,100,000			$ 19,100,000