Other Assets Loan Receivable and Allowance (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	$ 22,230,852atax_PropertyLoanReceivableGross	$ 22,191,515atax_PropertyLoanReceivableGross
Accrued interest	8,737,677atax_LoanInterestReceivable	8,324,812atax_LoanInterestReceivable
Loan loss reserves	(7,098,814)	(7,098,814)
Interest Allowance	(7,744,664)atax_InterestAllowance	(7,427,074)atax_InterestAllowance
Net taxable loans	16,125,051us-gaap_LoansReceivableNet	15,990,439us-gaap_LoansReceivableNet
Arbors at Hickory Ridge [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	191,264	191,264
Accrued interest	29,442	26,047
Loan loss reserves	0	0
Interest Allowance	0	0
Net taxable loans	220,706	217,311
Ashley Square [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	5,078,342	5,078,342
Accrued interest	2,557,178	2,455,660
Loan loss reserves	(3,596,342)	(3,596,342)
Interest Allowance	(2,557,178)	(2,455,660)
Net taxable loans	1,482,000	1,482,000
Avistar Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	274,496	274,496
Accrued interest	25,199	16,470
Loan loss reserves	0	0
Interest Allowance	0	0
Net taxable loans	299,695	290,966
Avistar Portolio-2 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	251,622	251,622
Accrued interest	23,099	15,097
Loan loss reserves	0	0
Interest Allowance	0	0
Net taxable loans	274,721	266,719
Cross Creek [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	7,033,587	6,976,087
Accrued interest	2,151,317	2,084,804
Loan loss reserves	(3,447,472)	(3,447,472)
Interest Allowance	(2,151,317)	(2,084,804)
Net taxable loans	3,586,115	3,528,615
Greens of Pine Glen [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	850,000	850,000
Accrued interest	258,376	231,342
Loan loss reserves	0	0
Interest Allowance	0	0
Net taxable loans	1,108,376	1,081,342
Foundation for Affordable Housing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	1,542,391	1,560,553	1,603,083
Accrued interest	0	1,735
Loan loss reserves	0	0
Interest Allowance	0	0
Net taxable loans	1,542,391	1,562,288
Lake Forest [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	4,618,704	4,618,704
Accrued interest	2,716,910	2,599,613
Loan loss reserves	(55,000)	(55,000)
Interest Allowance	(2,696,076)	(2,578,778)
Net taxable loans	4,584,538	4,584,539
Ohio Properties [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property loan receivable, outstanding balance	2,390,446	2,390,447
Accrued interest	976,156	894,044
Loan loss reserves	0	0
Interest Allowance	(340,093)	(307,832)
Net taxable loans	$ 3,026,509	$ 2,976,659

Interest receivable fully allowed for.

No definition available.

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received from a loan.

+ References

No definition available.

+ Details

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- 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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- Details

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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))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 2: 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(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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