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

The percentage of ownership of available-for-sale securities.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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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Data Type:	num:percentItemType
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- Definition

Number of Available for Sale Securities, Public Housing Authorities

+ 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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- 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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Public Housing Capital Fund Trusts Narrative Tagging (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Adverse change rate	10.00%atax_AdverseChangeRate
Available-for-sale Securities, Gross Unrealized Losses	$ (19,582)	$ 2,434,964
Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of Available for Sale Securities, Public Housing Authorities	3		3
Available for Sale Securities, not Including Premiums	59,308,398	65,264,703	65,264,703	59,300,000
Adverse change rate	10.00%
LIFERS [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Ownership Percentage			100.00%
LIFERS [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing			16,000,000	16,000,000
SPEARS [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
TOB Financing	44,700,000		49,000,000	49,000,000
Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	4.70%
Effective rate - minimum [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	4.20%
Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	8.30%
Effective rate - maximum [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	5.40%
10% adverse [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses	$ 2,300,000
10% adverse [Member] \| Effective rate - minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	5.10%
10% adverse [Member] \| Effective rate - minimum [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	4.70%
10% adverse [Member] \| Effective rate - maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	9.10%
10% adverse [Member] \| Effective rate - maximum [Member] \| Public housing capital fund trusts [Member]
Schedule of Available-for-sale Securities [Line Items]
Effective rate	6.00%