Document and Entity Information [Abstract] Document and Entity Information [Abstract] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Statement Of Financial Position [Abstract] Statement of Financial Position [Abstract] Statement, Scenario [Axis] Statement, Scenario [Axis] Series Forty Seven [Member] Series Forty Seven Series Forty Eight [Member] Series Forty Eight Series Forty Nine [Member] Series Forty Nine Assets [Abstract] ASSETS Real Estate Investment Property, Net INVESTMENTS IN OPERATING PARTNERSHIPS (Note D) Other Assets, Unclassified [Abstract] OTHER ASSETS Cash and Cash Equivalents, At Carrying Value Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value, Total Cash and cash equivalents, beginning Cash and cash equivalents, ending Notes, Loans and Financing Receivable, Net Notes receivable Notes, Loans and Financing Receivable, Net, Total Acquisition Cost Net Of Amortization Acquisition costs net Carrying amount as of the balance sheet date of acquisition cost, net amortization. Other Assets Other assets Other assets Assets Assets Assets Liabilities [Abstract] LIABILITIES Accounts Payable and Accrued Liabilities Accounts payable & accrued expenses Accounts Payable and Accrued Liabilities, Total Due To Affiliate Accounts payable affiliates Capital Contributions Payable Capital contributions payable Capital contributions payable Carrying value of the capital contribution payable to operating partnerships. Under the terms of the Partnership's investment in each Operating Partnership, the Partnership is required to make capital contributions to the Operating Partnerships. These contributions are payable in installments over several years upon each Operating Partnership achieving specified levels of construction and/or operations. Capital contributions payable Liabilities Liabilities Liabilities Partners Capital [Abstract] PARTNERS' CAPITAL (DEFICIT) Limited Partners Capital Account Units of limited partnership interest Limited partnership interest General Partners Capital Account General Partner General Partner Partners Capital Partners' capital (deficit) Partners' Capital Partners' capital (deficit) Partners' capital (deficit) Liabilities and Stockholders Equity Liabilities and Stockholders' Equity Liabilities and Stockholders' Equity Balance Sheet Parenthetical [Abstract] Balance Sheet Parenthetical [Abstract] Partners Capital Account, Distribution Per Unit Of Limited Partner Interest Beneficial assignee certificate, par value (in dollars per share) Limited Partners Capital Account, Units Authorized Units of limited partnership interest, authorized Limited Partners Capital Account, Units Issued BACs Sold Units of limited partnership interest, issued Limited Partners Capital Account, Units Outstanding Units of limited partnership interest, outstanding Income Statement [Abstract] Income Statement [Abstract] Revenues [Abstract] Revenues Income Interest Income, Operating Interest income Interest income Other Operating Income Other income Other income Revenues Revenues Revenues Income (Loss) From Equity Method Investments Share of loss from Operating Partnerships(Note D) Share of loss from Operating Partnerships(Note D) Share of Loss from Operating Partnerships Operating Expenses [Abstract] Expenses Professional Fees Professional fees Fund Management Fees Fund management fee, net (Note C) Annual fund management fee charged on all apartment complexes owned by the Operating Partnerships net of reporting fees. Amortization Of Acquisition Costs Amortization General and Administrative Expense General and administrative expenses General and administrative expenses Total Expenses Operating Expenses Operating expenses Total Amount of expenses incurred during the year by the entity. Net Income (Loss) Attributable To Parent Net loss NET LOSS NET LOSS Net Income (Loss) Allocated To Limited Partners Net loss allocated to assignees Net loss allocated to assignees Net Income (Loss) Allocated To General Partners Net loss allocated to general partner Net loss allocated to general partner Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic Net loss per BAC Net loss per BAC Statement Of Partners Capital [Abstract] Statement of Partners' Capital [Abstract] Related Party Transactions, By Related Party [Axis] Related Party Transactions, by Related Party [Axis] Assignees [Member] General Partner [Member] Statement Of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Net Cash Provided By (Used In) Operating Activities [Abstract] Cash flows from operating activities: Adjustments To Reconcile Net Income (Loss) To Cash Provided By (Used In) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash used in operating activities Amortization Amortization Amortization, Total Equity Method Investment, Dividends Or Distributions Distributions from Operating Partnerships Increase (Decrease) In Operating Capital [Abstract] Changes in assets and liabilities Increase (Decrease) In Accounts Receivable Decrease (Increase) in accounts receivable Decrease (Increase) in other assets Increase (Decrease) In Due To Affiliates Increase (Decrease) in accounts payable affiliates (Decrease) Increase in accounts payable affiliates Net Cash Provided By (Used In) Operating Activities Net cash (used in) provided by operating activities Net cash used in operating activities Net Cash Provided By (Used In) Investing Activities [Abstract] Cash flows from investing activities: Payments To Acquire Equity Method Investments Capital contributions paid to Operating Partnerships Capital contributions paid to Operating Partnerships Net Cash Provided By (Used In) Investing Activities Net cash (used in) provided by investing activities Net cash used in investing activities Cash and Cash Equivalents, Period Increase (Decrease) DECREASE IN CASH AND CASH EQUIVALENTS INCREASE (DECREASE) IN CASH ANDCASH EQUIVALENTS Organization, Consolidation and Presentation Of Financial Statements [Abstract] Organization [Abstract] Organization, Consolidation and Presentation Of Financial Statements Disclosure [Text Block] Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Accounting Policies [Abstract] General Policies [Abstract] Significant Accounting Policies [Text Block] Significant Accounting Policies [Text Block] Related Party Transactions [Abstract] Related Party Transactions [Abstract] Related Party Transactions Disclosure [Text Block] Related Party Transactions Disclosure [Text Block] Equity Method Investments and Joint Ventures [Abstract] Investments In Operating Partnerships [Abstract] Equity Method Investments Disclosure [Text Block] Equity Method Investments Disclosure [Text Block] Taxable Loss [Abstract] Taxable Loss [Abstract] Taxable Loss [Text Block] Taxable Loss [Text Block] entire disclosure of expected change in the Partnership's taxable loss for financial reporting purposes. This is primarily due to accounting differences in depreciation incurred by the Operating Partnerships and also differences between the equity method of accounting and IRS accounting methods. Income Tax Disclosure [Abstract] Income Taxes [Abstract] Income Tax Relating To Partnership Disclosure [Text Block] Income Tax Relating To Partnership Disclosure [Text Block] Description containing the income tax disclosure relating to Partnership that has elected to be treated as a pass-through entity for income tax purposes and, as such, is not subject to income taxes. Schedule Of Limited Partners Capital Account By Class [Table Text Block] Schedule of Limited Partners' Capital Account by Class [Table Text Block] Schedule Of Accumulated Amortization Of Acquisition Costs [Text Block] Schedule Of Accumulated Amortization Of Acquisition Costs [Text Block] Tabular disclosure for accumulated amortization of acquisition costs. Schedule Of Gross Management Fee [Table Text Block] Schedule Of Gross Management Fee [Table Text Block] Tabular disclosure for gross management fee. Schedule Of Management Fees Paid [Table Text Block] Schedule Of Management Fees Paid [Table Text Block] Tabular disclosure for management fees paid. Schedule Of Number Of Operating Partnerships [Table Text Block] Schedule Of Number Of Operating Partnerships [Table Text Block] Tabular disclosure for number of operating partnerships. Schedule Of Summarized Statement Of Operations In Operating Partnerships [Table Text Block] Schedule Of Summarized Statement Of Operations In Operating Partnerships [Table Text Block] Tabular disclosure for summarized statement of operations in operating partnerships. Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Closing Date Of Units Issued and Equity Raised Closing Date Closing date of units issued and equity raised. Limited Partners Contributed Capital Equity Raised Minimum Units Of Limited Partners Beneficial Interest For Sale Minimum Units Of Limited Partners Beneficial Interest For Sale Minimum units of limited partners interest for sale. Maximum Units Of Limited Partners Beneficial Interest For Sale Maximum Units Of Limited Partners Beneficial Interest For Sale Maximum units of limited partners interest for sale. Limited Partners Capital Account Per Units Limited Partners Capital Account Per Units Per unit rate of limited partners capital account. Limited Partners Capital Account Additional Units Registered For Sale Limited Partners Capital Account Additional Units Registered For Sale The additional number of limited partners units registered for sale. Accumulated Amortization Of Acquisition Costs Accumulated amortization of acquisition costs Accumulated amount of amortization of assets, and it reflects the allocation of capitalized costs associated with acquisition of business. Amortization Period Of Acquisition Costs Amortization Period Of Acquisition Costs Amortization period of capitalization acquisition costs. Impairment Loss Of Acquisition Costs Impairment Loss Of Acquisition Costs Amount of impairment loss of acquisition costs. Amortization Of Acquisition Cost Remaining Contractual Term Amortization Of Acquisition Cost Remaining Contractual Term Amortization of acquisition cost remaining contractual term in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Amortization Of Deferred Acquisition Costs Year One Amortization Of Deferred Acquisition Costs Amount of amortized deferred acquisition costs reported in first year. Amortization Period Of Capitalization Expenses Amortization Period Of Capitalization Expenses Amortization period of capitalization expenses. Impairment Loss Of Capitalized Expenses Impairment Loss Of Capitalized Expenses Amount of accumulated impairment loss related to as of the balance sheet date. Gross Management Fee Gross Management Fee Gross amount of management fee during the period. Management Fees Paid Management Fees Paid Amount of management fees paid during the period. Percentage Of Annual Management Fee Percentage Of Annual Management Fee The percentage of annual management fee. Number Of Operating Partnerships Number Of Operating Partnerships Number of operating partnerships. Operating Partnerships Rental Income Rental The amount of rental income by an operating partnerships of the entity. Operating Partnerships Interest and Other Income Interest and other The amount of interest and other income by an operating partnerships of the entity. Operating Partnerships Revenues Operating Partnerships Revenues Operating Partnerships Revenues The amount of revenues by an operating partnerships of the entity. Expenses [Abstract] Expenses Operating Partnerships Interest Expenses Interest The amount of interest expenses by an operating partnerships of the entity. Operating Partnerships Depreciation and Amortization Depreciation and amortization The amount of depreciation and amortization by an operating partnerships of the entity. Operating Partnerships Operating Expenses Operating expenses The amount of operating expenses by an operating partnerships of the entity. Operating Partnerships Total Expenses Operating Partnerships Total Expenses Operating Partnerships Total Expenses The amount of total expenses by an operating partnerships of the entity. Operating Partnerships Net Loss NET LOSS NET LOSS The amount of net loss by an operating partnerships of the entity. Operating Partnerships Net Loss Allocated To Parent Net loss allocated to Boston Capital Tax Credit Fund V L.P.* The amount of net loss allocated to parent by an operating partnerships of the entity. Operating Partnerships Net Loss Allocated To Other Partners Net loss allocated to other Partners The amount of net loss allocated to other partners by an operating partnerships of the entity. Income Loss Not Recognized Under Equity Method Accounting Income Loss Not Recognized Under Equity Method Accounting Amount of income loss not recognized under equity method accounting. Related Party [Domain] Related Party [Domain] Repayment From Operating Partnerships Repayment from Operating Partnerships Repayment from Operating Partnerships The cash inflow associated with repayment from operating partnerships. Other Noncash Investing and Financing Items [Abstract] Supplemental schedule of noncash investing and financing activities: Capital Contributions Due To Operating Limited Partnerships The Fund has increased its investments in operating partnerships and increased its capital contribution obligation to operating partnerships for capital contributions due to operating partnerships. The Fund has increased its investments in operating partnerships and increased its capital contribution obligation to operating partnerships for capital contributions due to operating partnerships. Amount of increased in investment with regard to capital contribution obligation to operating limited partnership by the entity during the period. Application Of Notes Receivable and Advances To Capital Contribution The Fund applied notes receivable and advances to its capital contribution obligation to operating partnerships. The Fund applied notes receivable and advances to its capital contribution obligation to operating partnerships. Amount of notes receivable and advances to its capital contribution obligation to operating limited partnerships by the entity during the period. Amortization Of Deferred Acquisition Costs Year Two Amount of amortized deferred acquisition costs reported in second year. Amortization Of Deferred Acquisition Costs Year Three Amount of amortized deferred acquisition costs reported in third year. Amortization Of Deferred Acquisition Costs Year Four Amount of amortized deferred acquisition costs reported in forth year. Amortization Of Deferred Acquisition Costs Year Five Amount of amortized deferred acquisition costs reported in fith year.