Available for sale securities carrying value disclosure mortgage backed securities.

No definition available.

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Namespace Prefix:	atax_
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Balance Type:	debit
Period Type:	instant

- Definition

Derivatives Sold.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of available for sale securities, held in a trust.

+ References

No definition available.

+ Details

Name:	atax_NumberOfAvailableForSaleSecuritiesHeldInTrust
Namespace Prefix:	atax_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

+ Details

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

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=atax_TrustPortfolioMBSBondsMember
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Mortgage-Backed Securities Narrative Tagging (Details)		1 Months Ended		6 Months Ended
Mortgage-Backed Securities Narrative Tagging (Details)	Jan. 31, 2016 USD ($) Integer	May 31, 2016 USD ($)	Jan. 31, 2016 USD ($) Integer	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)
Proceeds from Sale of Available-for-sale Securities		$ 5,200,000	$ 15,000,000	$ 9,295,000
Number of Available for Sale Securities, Held in a Trust \| Integer	3		3
Repayment of debt financing				13,487,639	$ 12,931,000
Available-for-sale Securities, Carrying Value, Mortgage-backed Securities				$ 0
Trust Portfolio M B S Bonds
Proceeds from Sale of Available-for-sale Securities	$ 15,000,000
Number of Available for Sale Securities, Held in a Trust \| Integer	3		3
Repayment of debt financing	$ 11,900,000
Proceeds from Sale of Available-for-sale Securities	11,000,000
Available-for-sale Securities, Gross Realized Gain (Loss)	$ 0