| Label |
Element |
Value |
| Risk/Return: |
rr_RiskReturnAbstract |
|
|
| Registrant Name |
dei_EntityRegistrantName |
BLACKROCK MUNICIPAL BOND FUND, INC.
|
|
| Prospectus Date |
rr_ProspectusDate |
Oct. 28, 2015
|
|
| Supplement [Text Block] |
bmbfi5_SupplementTextBlock |
BlackRock Municipal Bond Fund, Inc.
BlackRock Short-Term Municipal Fund
(the “Fund”)
Investor and Institutional Shares Supplement dated October 14, 2016
to the Prospectus dated October 28, 2015 Effective as of October 14, 2016, BlackRock Advisors, LLC (“BlackRock”) has agreed to adjust the caps on total expenses to reduce the net expenses paid by shareholders of the Fund. To achieve these expense caps, BlackRock has agreed to waive and/or reimburse fees and/or expenses if the Fund’s annual fund operating expenses, excluding certain expenses described in the prospectus, exceed a certain limit for the Fund’s Investor A, Investor C and Institutional Shares. Accordingly, the Fund’s Prospectus is amended as follows: The section of the Fund’s Prospectus entitled “Fund Overview — Key Facts About BlackRock Short-Term Municipal Fund — Fees and Expenses of the Fund” is deleted in its entirety and replaced with the following: Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. More information about these and other discounts is available from your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. (“PNC”) and their respective affiliates) (each a “Financial Intermediary”) and in the “Details About the Share Classes” section on page 37 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-69 of Part II of the Fund’s Statement of Additional Information. Shareholder Fees
(fees paid directly from your investment)
| | | | Investor A
Shares | | Investor C
Shares | | Institutional
Shares | Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price) | | | | 3.00% | | None | | None | Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower) | | | | None1 | | 1.00%2 | | None |
Annual Fund Operating Expenses
(expenses that you pay each year as a
percentage of the value of your investment)
| | | | Investor A
Shares | | Investor C
Shares | | Institutional
Shares | Management Fee | | | | 0.33% | | 0.33% | | 0.33% | Distribution and/or Service (12b-1) Fees | | | | 0.25% | | 1.00% | | None | Other Expenses | | | | 0.12% | | 0.14% | | 0.18% | Total Annual Fund Operating Expenses | | | | 0.70% | | 1.47% | | 0.51% | Fee Waivers and/or Expense Reimbursements3 | | | | (0.09)% | | (0.11)% | | (0.15)% | Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements3 | | | | 0.61% | | 1.36% | | 0.36% |
| 1 | | A contingent deferred sales charge (“CDSC”) of 0.50% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase of an investment of $250,000 or more. | | 2 | | There is no CDSC on Investor C Shares after one year. | | 3 | | As described in the “Management of the Funds” section of the Fund’s prospectus on page 52, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.61% (for Investor A Shares), 1.36% (for Investor C Shares) and 0.36% (for Institutional Shares) of average daily net assets through October 31, 2017. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the BlackRock Municipal Bond Fund, Inc. or by a vote of a majority of the outstanding securities of the Fund. | Example: This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: | | | | 1 Year | | 3 Years | | 5 Years | | 10 Years | Investor A Shares | | | | $ | 360 | | | $ | 508 | | | $ | 669 | | | $ | 1,136 | | Investor C Shares | | | | $ | 238 | | | $ | 454 | | | $ | 792 | | | $ | 1,748 | | Institutional Shares | | | | $ | 37 | | | $ | 148 | | | $ | 270 | | | $ | 626 | |
You would pay the following expenses if you did not redeem your shares: | | | | 1 Year | | 3 Years | | 5 Years | | 10 Years | Investor C Shares | | | | $ | 138 | | | $ | 454 | | | $ | 792 | | | $ | 1,748 | |
Portfolio Turnover: The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 72% of the average value of its portfolio.
|
|
| BlackRock Short-Term Municipal Fund |
|
|
|
| Risk/Return: |
rr_RiskReturnAbstract |
|
|
| Supplement [Text Block] |
bmbfi5_SupplementTextBlock |
BlackRock Municipal Bond Fund, Inc.
BlackRock Short-Term Municipal Fund
(the “Fund”)
Investor and Institutional Shares Supplement dated October 14, 2016
to the Prospectus dated October 28, 2015 Effective as of October 14, 2016, BlackRock Advisors, LLC (“BlackRock”) has agreed to adjust the caps on total expenses to reduce the net expenses paid by shareholders of the Fund. To achieve these expense caps, BlackRock has agreed to waive and/or reimburse fees and/or expenses if the Fund’s annual fund operating expenses, excluding certain expenses described in the prospectus, exceed a certain limit for the Fund’s Investor A, Investor C and Institutional Shares. Accordingly, the Fund’s Prospectus is amended as follows: The section of the Fund’s Prospectus entitled “Fund Overview — Key Facts About BlackRock Short-Term Municipal Fund — Fees and Expenses of the Fund” is deleted in its entirety and replaced with the following: Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. More information about these and other discounts is available from your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. (“PNC”) and their respective affiliates) (each a “Financial Intermediary”) and in the “Details About the Share Classes” section on page 37 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-69 of Part II of the Fund’s Statement of Additional Information. Shareholder Fees
(fees paid directly from your investment)
| | | | Investor A
Shares | | Investor C
Shares | | Institutional
Shares | Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price) | | | | 3.00% | | None | | None | Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower) | | | | None1 | | 1.00%2 | | None |
Annual Fund Operating Expenses
(expenses that you pay each year as a
percentage of the value of your investment)
| | | | Investor A
Shares | | Investor C
Shares | | Institutional
Shares | Management Fee | | | | 0.33% | | 0.33% | | 0.33% | Distribution and/or Service (12b-1) Fees | | | | 0.25% | | 1.00% | | None | Other Expenses | | | | 0.12% | | 0.14% | | 0.18% | Total Annual Fund Operating Expenses | | | | 0.70% | | 1.47% | | 0.51% | Fee Waivers and/or Expense Reimbursements3 | | | | (0.09)% | | (0.11)% | | (0.15)% | Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements3 | | | | 0.61% | | 1.36% | | 0.36% |
| 1 | | A contingent deferred sales charge (“CDSC”) of 0.50% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase of an investment of $250,000 or more. | | 2 | | There is no CDSC on Investor C Shares after one year. | | 3 | | As described in the “Management of the Funds” section of the Fund’s prospectus on page 52, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.61% (for Investor A Shares), 1.36% (for Investor C Shares) and 0.36% (for Institutional Shares) of average daily net assets through October 31, 2017. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the BlackRock Municipal Bond Fund, Inc. or by a vote of a majority of the outstanding securities of the Fund. | Example: This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: | | | | 1 Year | | 3 Years | | 5 Years | | 10 Years | Investor A Shares | | | | $ | 360 | | | $ | 508 | | | $ | 669 | | | $ | 1,136 | | Investor C Shares | | | | $ | 238 | | | $ | 454 | | | $ | 792 | | | $ | 1,748 | | Institutional Shares | | | | $ | 37 | | | $ | 148 | | | $ | 270 | | | $ | 626 | |
You would pay the following expenses if you did not redeem your shares: | | | | 1 Year | | 3 Years | | 5 Years | | 10 Years | Investor C Shares | | | | $ | 138 | | | $ | 454 | | | $ | 792 | | | $ | 1,748 | |
Portfolio Turnover: The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 72% of the average value of its portfolio.
|
|
| Expense [Heading] |
rr_ExpenseHeading |
Fees and Expenses of the Fund
|
|
| Expense Narrative [Text Block] |
rr_ExpenseNarrativeTextBlock |
This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. More information about these and other discounts is available from your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. (“PNC”) and their respective affiliates) (each a “Financial Intermediary”) and in the “Details About the Share Classes” section on page 37 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-69 of Part II of the Fund’s Statement of Additional Information.
|
|
| Shareholder Fees Caption [Text] |
rr_ShareholderFeesCaption |
Shareholder Fees
(fees paid directly from your investment)
|
|
| Operating Expenses Caption [Text] |
rr_OperatingExpensesCaption |
Annual Fund Operating Expenses
(expenses that you pay each year as a
percentage of the value of your investment)
|
|
| Fee Waiver or Reimbursement over Assets, Date of Termination |
rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination |
October 31, 2017
|
|
| Portfolio Turnover [Heading] |
rr_PortfolioTurnoverHeading |
Portfolio Turnover:
|
|
| Portfolio Turnover [Text Block] |
rr_PortfolioTurnoverTextBlock |
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 72% of the average value of its portfolio.
|
|
| Portfolio Turnover, Rate |
rr_PortfolioTurnoverRate |
72.00%
|
|
| Expenses Deferred Charges [Text Block] |
rr_ExpensesDeferredChargesTextBlock |
A contingent deferred sales charge (“CDSC”) of 0.50% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase of an investment of $250,000 or more.
|
|
| Expense Breakpoint Discounts [Text] |
rr_ExpenseBreakpointDiscounts |
You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates.
|
|
| Expense Breakpoint, Minimum Investment Required [Amount] |
rr_ExpenseBreakpointMinimumInvestmentRequiredAmount |
$ 50,000
|
|
| Expense Example [Heading] |
rr_ExpenseExampleHeading |
Example:
|
|
| Expense Example Narrative [Text Block] |
rr_ExpenseExampleNarrativeTextBlock |
This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
|
|
| Expense Example, No Redemption, By Year, Caption [Text] |
rr_ExpenseExampleNoRedemptionByYearCaption |
You would pay the following expenses if you did not redeem your shares:
|
|
| BlackRock Short-Term Municipal Fund | Investor A Shares |
|
|
|
| Risk/Return: |
rr_RiskReturnAbstract |
|
|
| Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price) |
rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice |
3.00%
|
|
| Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower) |
rr_MaximumDeferredSalesChargeOverOfferingPrice |
none
|
[1] |
| Management Fee |
rr_ManagementFeesOverAssets |
0.33%
|
|
| Distribution and/or Service (12b-1) Fees |
rr_DistributionAndService12b1FeesOverAssets |
0.25%
|
|
| Other Expenses |
rr_OtherExpensesOverAssets |
0.12%
|
|
| Total Annual Fund Operating Expenses |
rr_ExpensesOverAssets |
0.70%
|
|
| Fee Waivers and/or Expense Reimbursements |
rr_FeeWaiverOrReimbursementOverAssets |
(0.09%)
|
[2] |
| Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements |
rr_NetExpensesOverAssets |
0.61%
|
[2] |
| 1 Year |
rr_ExpenseExampleYear01 |
$ 360
|
|
| 3 Years |
rr_ExpenseExampleYear03 |
508
|
|
| 5 Years |
rr_ExpenseExampleYear05 |
669
|
|
| 10 Years |
rr_ExpenseExampleYear10 |
$ 1,136
|
|
| BlackRock Short-Term Municipal Fund | Investor C Shares |
|
|
|
| Risk/Return: |
rr_RiskReturnAbstract |
|
|
| Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price) |
rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice |
none
|
|
| Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower) |
rr_MaximumDeferredSalesChargeOverOfferingPrice |
1.00%
|
[3] |
| Management Fee |
rr_ManagementFeesOverAssets |
0.33%
|
|
| Distribution and/or Service (12b-1) Fees |
rr_DistributionAndService12b1FeesOverAssets |
1.00%
|
|
| Other Expenses |
rr_OtherExpensesOverAssets |
0.14%
|
|
| Total Annual Fund Operating Expenses |
rr_ExpensesOverAssets |
1.47%
|
|
| Fee Waivers and/or Expense Reimbursements |
rr_FeeWaiverOrReimbursementOverAssets |
(0.11%)
|
[2] |
| Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements |
rr_NetExpensesOverAssets |
1.36%
|
[2] |
| 1 Year |
rr_ExpenseExampleYear01 |
$ 238
|
|
| 3 Years |
rr_ExpenseExampleYear03 |
454
|
|
| 5 Years |
rr_ExpenseExampleYear05 |
792
|
|
| 10 Years |
rr_ExpenseExampleYear10 |
1,748
|
|
| 1 Year |
rr_ExpenseExampleNoRedemptionYear01 |
138
|
|
| 3 Years |
rr_ExpenseExampleNoRedemptionYear03 |
454
|
|
| 5 Years |
rr_ExpenseExampleNoRedemptionYear05 |
792
|
|
| 10 Years |
rr_ExpenseExampleNoRedemptionYear10 |
$ 1,748
|
|
| BlackRock Short-Term Municipal Fund | Institutional Shares |
|
|
|
| Risk/Return: |
rr_RiskReturnAbstract |
|
|
| Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price) |
rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice |
none
|
|
| Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower) |
rr_MaximumDeferredSalesChargeOverOfferingPrice |
none
|
|
| Management Fee |
rr_ManagementFeesOverAssets |
0.33%
|
|
| Distribution and/or Service (12b-1) Fees |
rr_DistributionAndService12b1FeesOverAssets |
none
|
|
| Other Expenses |
rr_OtherExpensesOverAssets |
0.18%
|
|
| Total Annual Fund Operating Expenses |
rr_ExpensesOverAssets |
0.51%
|
|
| Fee Waivers and/or Expense Reimbursements |
rr_FeeWaiverOrReimbursementOverAssets |
(0.15%)
|
[2] |
| Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements |
rr_NetExpensesOverAssets |
0.36%
|
[2] |
| 1 Year |
rr_ExpenseExampleYear01 |
$ 37
|
|
| 3 Years |
rr_ExpenseExampleYear03 |
148
|
|
| 5 Years |
rr_ExpenseExampleYear05 |
270
|
|
| 10 Years |
rr_ExpenseExampleYear10 |
$ 626
|
|
|
|
