2.4.0.8000080 - Disclosure - 1. Basis of Presentationtruefalsefalse1false falsefalseD130331_130629http://www.sec.gov/CIK0000897315duration2013-03-31T00:00:002013-06-29T00:00:001true 1us-gaap_DisclosureTextBlockAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Notes2false 2us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse001.      Basis of Presentation   The accompanying unaudited financial statements of American Tax Credit Trust, a Delaware statutory business trust Series I (the Trust) have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information. They do not include all information and footnotes required by GAAP for complete financial statements. The results of operations are impacted, in part, by the combined results of operations of the Trusts investee partnerships (the Local Partnerships), which are provided by the general partners of the Local Partnerships (the Local General Partners) on an unaudited basis during interim periods. Accordingly, the accompanying unaudited financial statements are dependent on such unaudited information. In the opinion of the manager of the Trust (the Manager), the accompanying unaudited financial statements include all adjustments necessary to present fairly the financial position as of June 29, 2013 and the results of operations and cash flows for the interim periods presented. All adjustments are of a normal recurring nature. The results of operations for the three months ended June 29, 2013 are not necessarily indicative of the results that may be expected for the entire year.falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).No definition available.false01. Basis of Presentationfalse1. Basis of PresentationUnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://atctixbrl.com/20130629/role/idr_Disclosure1BasisOfPresentation12