Variable Interest Entities Consolidating Income Statement (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues [Abstract]
Property revenues	$ 5,106,369	$ 3,951,216
Investment income	7,979,784us-gaap_InvestmentIncomeNet	6,205,558us-gaap_InvestmentIncomeNet
Gain on sale and retirement of bonds	0atax_GainOnSaleAndRetirementOfBonds	2,835,243atax_GainOnSaleAndRetirementOfBonds
Interest Income, Operating	224,540us-gaap_InterestIncomeOperating	208,823us-gaap_InterestIncomeOperating
Revenues	13,310,693us-gaap_Revenues	13,200,840us-gaap_Revenues
Expenses [Abstract]
Real estate operating (exclusive of items shown below)	2,958,605atax_RealEstateOperatingExpense	2,100,293atax_RealEstateOperatingExpense
Depreciation and amortization	2,031,898	1,613,346
Interest	3,989,121us-gaap_InterestExpense	2,169,549us-gaap_InterestExpense
General and administrative	1,807,481us-gaap_GeneralAndAdministrativeExpense	1,270,926us-gaap_GeneralAndAdministrativeExpense
Total expenses	10,787,105us-gaap_CostsAndExpenses	7,154,114us-gaap_CostsAndExpenses
Net income (loss)	2,523,588us-gaap_ProfitLoss	6,046,726us-gaap_ProfitLoss
Net income (loss) attributable to noncontrolling interest	(891)	(103)
Net income (loss) - America First Tax Exempt Investors, L.P.	2,524,479us-gaap_OperatingIncomeLoss	6,046,829us-gaap_OperatingIncomeLoss
Partnership [Member]
Revenues [Abstract]
Property revenues	4,302,301	3,150,344
Investment income	8,210,394	6,438,835
Gain on sale and retirement of bonds		2,835,243
Interest Income, Operating	224,540	208,823
Revenues	12,737,235	12,633,245
Expenses [Abstract]
Real estate operating (exclusive of items shown below)	2,471,030	1,650,647
Depreciation and amortization	1,794,814	1,382,626
Interest	3,994,156	2,169,549
General and administrative	1,807,481	1,270,926
Total expenses	10,067,481	6,473,748
Net income (loss)	2,669,754	6,159,497
Net income (loss) attributable to noncontrolling interest	(891)	(103)
Net income (loss) - America First Tax Exempt Investors, L.P.	2,670,645	6,159,600
Consolidated VIEs [Member]
Revenues [Abstract]
Property revenues	804,068	800,872
Investment income	0	0
Gain on sale and retirement of bonds		0
Interest Income, Operating	0	0
Revenues	804,068	800,872
Expenses [Abstract]
Real estate operating (exclusive of items shown below)	487,575	449,646
Depreciation and amortization	243,729	237,440
Interest	569,934	557,884
General and administrative	0	0
Total expenses	1,301,238	1,244,970
Net income (loss)	(497,170)	(444,098)
Net income (loss) attributable to noncontrolling interest	0	0
Net income (loss) - America First Tax Exempt Investors, L.P.	(497,170)	(444,098)
Consolidations, Eliminations for VIEs [Member]
Revenues [Abstract]
Property revenues	0	0
Investment income	(230,610)	(233,277)
Gain on sale and retirement of bonds		0
Interest Income, Operating	0	0
Revenues	(230,610)	(233,277)
Expenses [Abstract]
Real estate operating (exclusive of items shown below)	0	0
Depreciation and amortization	(6,645)	(6,720)
Interest	(574,969)	(557,884)
General and administrative	0	0
Total expenses	(581,614)	(564,604)
Net income (loss)	351,004	331,327
Net income (loss) attributable to noncontrolling interest	0	0
Net income (loss) - America First Tax Exempt Investors, L.P.	$ 351,004	$ 331,327

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Real estate operating expenses normally associated with the operation of multi-family housing exclusive of interest expense, general and administrative expenses, and deprecreciation, depletion and amortization expenses.

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Total costs of sales and operating expenses for the period.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The net result for the period of deducting operating expenses from operating revenues.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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