Organization	12 Months Ended
Mar. 31, 2012
Accounting Policies [Abstract]
Business Description and Basis of Presentation [Text Block]	1. Organization Boston Financial Tax Credit Fund Plus, A Limited Partnership (the "Fund") is a Massachusetts limited partnership organized to invest as a limited partner or member in other limited partnerships or limited liability companies (collectively, "Local Limited Partnerships") which own and operate apartment complexes which are eligible for low income housing tax credits (“Tax Credits”) which may be applied against the federal income tax liability of an investor. The Fund also invested in, for the benefit of the Class B Limited Partners, United States Treasury obligations from which the interest coupons have been stripped or in such interest coupons themselves (collectively, "Treasury STRIPS"). The Fund used approximately 28% of the Class B Limited Partners' capital contributions to purchase Treasury STRIPS with maturities of 13 to 18 years, with a total redemption amount equal to the Class B Limited Partners' capital contributions. The Fund’s objectives are to: (i) provide annual tax benefits in the form of Tax Credits which Limited Partners may use to offset their federal income tax liability; (ii) preserve and protect the Fund’s capital committed to Local Limited Partnerships; (iii) provide cash distributions from operations of Local Limited Partnerships; (iv) provide cash distributions from sale or refinancing transactions with the possibility of long term capital appreciation; and (v) provide cash distributions derived from investment in Treasury STRIPS to Class B Limited Partners after a period of approximately thirteen to eighteen years equal to their capital contributions. The General Partners of the Fund are Arch Street VIII, Inc., which serves as the Managing General Partner, and Arch Street VI Limited Partnership. ALZA Corporation is the ClassALimited Partner of Arch Street VI Limited Partnership, Boston Financial BFG Investments, LLC is the Class B Limited Partner of Arch Street VI Limited Partnership and Arch Street VIII, Inc. is the general partner of Arch Street VI Limited Partnership. The fiscal year of the Fund ends on March 31. The Fund offered two classes of limited partnership interests - Class A limited partnership interests, represented by ClassAUnits, and Class B limited partnership interests, represented by Class B Units. The capital contributions of ClassALimited Partners available for investment by the Fund are invested entirely in Local Limited Partnerships. The capital contributions of Class B Limited Partners available for investment by the Fund are invested partially in Local Limited Partnerships and partially in Treasury STRIPS. The Agreement of Limited Partnership (the “Partnership Agreement”) authorized the sale of up to 100,000 Units of limited partnership interests ("Units") at $1,000 per Unit. The Fund raised $37,932,300 ("Gross Proceeds"), net of discounts of $700, through the sale of 34,643 ClassAUnits and 3,290 Class B Units. The offering of Units terminated on January 11, 1993. No further sale of Units is expected. The Managing General Partner initially designated 4% of the Adjusted Gross Proceeds (which generally means Gross Proceeds minus the amounts committed to the acquisition of Treasury STRIPS) as Reserves, as defined in the Partnership Agreement. The Reserves were established to be used for working capital of the Fund and contingencies related to the ownership of Local Limited Partnership interests. The Managing General Partner may increase or decrease such Reserves from time to time, as it deems appropriate. At March 31, 2012 and 2011 approximately $1,452,000 and $1,356,000, respectively, has been designated as Reserves. Generally, profits, losses, tax credits and cash flow from operations are allocated 99% to the Limited Partners and 1% to the General Partners. Net proceeds from a sale of the Fund’s interest in a Local Limited Partnership or refinancing of a Local Limited Partnership’s debt will be allocated 95% to the Limited Partners and 5% to the General Partners, after certain priority payments. The General Partners may have an obligation to fund deficits in their capital accounts, subject to limits set forth in the Partnership Agreement. However, to the extent that the General Partners’ capital accounts are in a deficit position, certain items of net income may be allocated to the General Partners in accordance with the Partnership Agreement. Because each class of Limited Partners had a different amount of its capital contribution available for investment by the Fund in Local Limited Partnerships (100% for Class A Limited Partners and approximately 72% for Class B Limited Partners), the two classes of Limited Partners have different percentage participation as to cash distributions, sale or refinancing proceeds and allocation of profits, losses and credits attributable to investments in Local Limited Partnerships. As such, profits and losses for financial reporting purposes are allocated 1% to the General Partners, 92.66% to the ClassALimited Partners and 6.34% to the Class B Limited Partners. All profits and losses and cash distributions attributable to Treasury STRIPS are allocable only to Class B Limited Partners.

Organization

12 Months Ended

Mar. 31, 2012

Business Description and Basis of Presentation [Text Block]

1. Organization

Boston Financial Tax Credit Fund Plus, A Limited Partnership (the "Fund") is a Massachusetts limited partnership organized to invest as a limited partner or member in other limited partnerships or limited liability companies (collectively, "Local Limited Partnerships") which own and operate apartment complexes which are eligible for low income housing tax credits (“Tax Credits”) which may be applied against the federal income tax liability of an investor. The Fund also invested in, for the benefit of the Class B Limited Partners, United States Treasury obligations from which the interest coupons have been stripped or in such interest coupons themselves (collectively, "Treasury STRIPS"). The Fund used approximately 28% of the Class B Limited Partners' capital contributions to purchase Treasury STRIPS with maturities of 13 to 18 years, with a total redemption amount equal to the Class B Limited Partners' capital contributions. The Fund’s objectives are to: (i) provide annual tax benefits in the form of Tax Credits which Limited Partners may use to offset their federal income tax liability; (ii) preserve and protect the Fund’s capital committed to Local Limited Partnerships; (iii) provide cash distributions from operations of Local Limited Partnerships; (iv) provide cash distributions from sale or refinancing transactions with the possibility of long term capital appreciation; and (v) provide cash distributions derived from investment in Treasury STRIPS to Class B Limited Partners after a period of approximately thirteen to eighteen years equal to their capital contributions. The General Partners of the Fund are Arch Street VIII, Inc., which serves as the Managing General Partner, and Arch Street VI Limited Partnership. ALZA Corporation is the ClassALimited Partner of Arch Street VI Limited Partnership, Boston Financial BFG Investments, LLC is the Class B Limited Partner of Arch Street VI Limited Partnership and Arch Street VIII, Inc. is the general partner of Arch Street VI Limited Partnership. The fiscal year of the Fund ends on March 31.

The Fund offered two classes of limited partnership interests - Class A limited partnership interests, represented by ClassAUnits, and Class B limited partnership interests, represented by Class B Units. The capital contributions of ClassALimited Partners available for investment by the Fund are invested entirely in Local Limited Partnerships. The capital contributions of Class B Limited Partners available for investment by the Fund are invested partially in Local Limited Partnerships and partially in Treasury STRIPS.

The Agreement of Limited Partnership (the “Partnership Agreement”) authorized the sale of up to 100,000 Units of limited partnership interests ("Units") at $1,000 per Unit. The Fund raised $37,932,300 ("Gross Proceeds"), net of discounts of $700, through the sale of 34,643 ClassAUnits and 3,290 Class B Units. The offering of Units terminated on January 11, 1993. No further sale of Units is expected.

The Managing General Partner initially designated 4% of the Adjusted Gross Proceeds (which generally means Gross Proceeds minus the amounts committed to the acquisition of Treasury STRIPS) as Reserves, as defined in the Partnership Agreement. The Reserves were established to be used for working capital of the Fund and contingencies related to the ownership of Local Limited Partnership interests. The Managing General Partner may increase or decrease such Reserves from time to time, as it deems appropriate. At March 31, 2012 and 2011 approximately $1,452,000 and $1,356,000, respectively, has been designated as Reserves.

Generally, profits, losses, tax credits and cash flow from operations are allocated 99% to the Limited Partners and 1% to the General Partners. Net proceeds from a sale of the Fund’s interest in a Local Limited Partnership or refinancing of a Local Limited Partnership’s debt will be allocated 95% to the Limited Partners and 5% to the General Partners, after certain priority payments. The General Partners may have an obligation to fund deficits in their capital accounts, subject to limits set forth in the Partnership Agreement. However, to the extent that the General Partners’ capital accounts are in a deficit position, certain items of net income may be allocated to the General Partners in accordance with the Partnership Agreement.

Because each class of Limited Partners had a different amount of its capital contribution available for investment by the Fund in Local Limited Partnerships (100% for Class A Limited Partners and approximately 72% for Class B Limited Partners), the two classes of Limited Partners have different percentage participation as to cash distributions, sale or refinancing proceeds and allocation of profits, losses and credits attributable to investments in Local Limited Partnerships. As such, profits and losses for financial reporting purposes are allocated 1% to the General Partners, 92.66% to the ClassALimited Partners and 6.34% to the Class B Limited Partners. All profits and losses and cash distributions attributable to Treasury STRIPS are allocable only to Class B Limited Partners.