2.2.0.25truefalse0100000 - Document - Risk/Return Summary {Unlabeled}falsefalsetrue1falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : Viking Tax-Free Fund for Montana 5/1/2010 - 4/30/2011 USD ($) $TwelveMonthsEnded_30Apr2011_S000003821_Memberhttp://www.sec.gov/CIK0001082744duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsevmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://integrityvikingfunds.com/role/riskreturnsummary1falsefalsefalse00Viking Tax-Free Fund for MontanaViking Tax-Free Fund for Montanafalsefalsefalsefalsefalse1falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : Viking Tax-Free Fund for Montana 5/1/2010 - 4/30/2011 USD ($) $TwelveMonthsEnded_30Apr2011_S000003821_Memberhttp://www.sec.gov/CIK0001082744duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsevmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseViking Tax-Free Fund for Montana3false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00VIKING TAX-FREE FUND FOR MONTANA&#8212;SUMMARYfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]4false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Investment ObjectivefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]5false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The Fund seeks the highest level of current income that is exempt from federal and Montana personal income taxes and is consistent with preservation of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]6false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and Expenses of the FundfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. 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 may indicate higher transaction costs. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]7false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This 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 with respect to purchases of shares of the Fund if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund or in other funds in the Integrity/Viking family of funds. More information about these and other discounts is available from your financial professional and in "Your Account" on page 23 of the Fund's prospectus and "Buying and Selling Shares" on page 30 of the Fund's statement of additional information.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]8false0rr_ShareholderFeesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Shareholder Fees (fees paid directly from your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subsection table falsefalseShareholder Fees Caption [Text]9false0rr_ShareholderFeesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForMontanafalsefalse0200100 - Schedule - Shareholder Feestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for MontanaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03750.0375falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricetruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.03750.0375falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)2falseRowprimaryElement*5false0rr_MaximumDeferredSalesChargeOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01500.0150falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)0rr_MaximumDeferredSalesChargeOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01500.0150falsefalsefalsetruefalseOthernanafalsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)3falseRowprimaryElement*6false0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Sales Charge (Load) Imposed on Reinvested Dividends[and other Distributions] (as a percentage of ____)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 3 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends4falseRowprimaryElement*7false0rr_RedemptionFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonPositivePure4Typepure"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph b -Subsection instructions falsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)0rr_RedemptionFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)5falseRowprimaryElement*8false0rr_ExchangeFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureExchange Fee includes the maximum fee charged for any exchange or transfer of interest from the Fund to another fund. The Fund may include in a footnote to the table, if applicable, a tabular presentation of the range of exchange fees or a narrative explanation of the fees.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph c -Subsection instructions falsefalseExchange Fee0rr_ExchangeFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseExchange Fee15Shareholder Fees UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ShareholderFeesData.No authoritative reference available.falsefalseShareholder Fees [Table]10false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]11false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForMontanafalsefalse0200200 - Schedule - Annual Fund Operating Expensestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for MontanaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00500.0050falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement Fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00500.0050falsefalsefalsetruefalseOthernanafalsefalseManagement Fees2falseRowprimaryElement*5false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00250.0025falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and Service (12b-1) Fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and Service (12b-1) Fees3falseRowprimaryElement*6false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00600.0060falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther Expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00600.0060falsefalsefalsetruefalseOthernanafalsefalseOther Expenses4falseRowprimaryElement*7false0rr_AcquiredFundFeesAndExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00010.0001[1]falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseAcquired Fund Fees and Expenses0rr_AcquiredFundFeesAndExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[1]1truetruetrue0.00010.0001falsefalsefalsetruefalseOthernanafalsefalseAcquired Fund Fees and Expenses5falseRowprimaryElement*8false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01360.0136falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal Annual Fund Operating Expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01360.0136falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses6falseRowprimaryElement*9false0rr_FeeWaiverOrReimbursementOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0028-0.0028[2]falsefalsefalsetruefalseOtherrr:NonPositivePure4TypepureTotal Annual Fund Operating Expenses. If there were expense reimbursement or fee waiver arrangements that reduced any Fund operating expenses and will continue to reduce them for no less than one year from the effective date of the Fund's registration statement, a Fund may add two captions to the table one caption showing the amount of the expense reimbursement or fee waiver, and a second caption showing the Fund's net expenses after subtracting the fee reimbursement or expense waiver from the total fund operating expenses. The Fund should place these additional captions directly below the "Total Annual Fund Operating Expenses" caption of the table and should use appropriate descriptive captions, such as "Fee Waiver [and/or Expense Reimbursement]" and "Total Annual Fund Operating Expenses After Fee Waiver [and/or Expense Reimbursement]," respectively. If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseFee Waivers and Expense Reimbursements0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[2]1truetruetrue-0.0028-0.0028falsefalsefalsetruefalseOthernanafalsefalseFee Waivers and Expense Reimbursements7falseRowprimaryElement*10false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01080.0108falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01080.0108falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements1Acquired Fund Fees and Expenses are the indirect costs of investing in other investment companies. The Total Annual Fund Operating Expenses do not correlate with the ratio of expenses to average net assets in the Fund's financial highlights, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.2The Fund's investment adviser has contractually agreed to waive fees and reimburse expenses from April 30, 2011 through April 29, 2012 so that Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements (excluding taxes, brokerage fees, commissions, extraordinary and non-recurring expenses, and Acquired Fund Fees and Expenses) do not exceed 1.07% of average daily net assets. If the Fund incurred extraordinary or non-recurring expenses, Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements would be higher than what is shown in the table above. This expense limitation agreement may only be terminated or modified prior to April 29, 2012 with the approval of the Fund's Board of Trustees.17Annual Fund Operating Expenses UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]12false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]13false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This Example is intended to help you compare the cost of investing in the Fund with the costs 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:falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]14false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>truehttp://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForMontanafalsefalse0200300 - Schedule - Expense Example {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue482482falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 YearfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue770770falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 YearsfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10891089falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 YearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue20352035falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 YearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for MontanaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue482482falsefalsefalsetruefalse2truefalsetrue770770falsefalsefalsetruefalse3truefalsetrue10891089falsefalsefalsetruefalse4truefalsetrue20352035falsefalsefalsetruefalseOthernanafalsefalseViking Tax-Free Fund for Montana41Expense Example (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]15false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio TurnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]16false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The 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 Fund 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 25.34% of the average value of its portfolio.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]17false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment StrategiesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]18false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>To pursue its objective, the Fund normally invests:</p><p>&#8226; at least 80% of its net assets (including any borrowings for investment purposes) in municipal securities that pay interest free from federal income taxes, including the federal alternative minimum tax;</p><p>&#8226; at least 80% of its net assets (including any borrowings for investment purposes) in municipal securities that pay interest free from Montana personal income taxes, although the Fund tries to invest all of its assets in these securities.</p><p>Municipal bonds are debt securities issued by or on behalf of states, territories, and possessions of the United States and their political subdivisions, agencies, authorities, and instrumentalities. The two general classifications of municipal bonds are "general obligation" and "revenue" bonds. General obligation bonds are secured by the issuer's pledge of its faith, credit, and taxing power for the payment of principal and interest. Revenue bonds are payable only from the revenues derived from a particular facility or class of facilities or, in some cases, from the proceeds of a special excise tax or other specific revenue source.</p><p>The investment manager actively manages the Fund's portfolio by selecting securities that it believes will provide the best balance between risk and return within the Fund's range of allowable investments. The investment manager will consider selling a security with deteriorating credit or limited upside potential compared to other available bonds.</p><p>The Fund may invest up to 30% of its net assets in U.S. territorial obligations (including qualifying obligations of Puerto Rico, the U.S. Virgin Islands, and Guam), the interest on which is exempt from federal and Montana personal income taxes. The Fund may invest up to 20% of its net assets in private activity bonds (which are revenue bonds that finance privately operated facilities), the interest on which is a tax preference item for purposes of the federal alternative minimum tax.</p><p>The Fund may invest more than 25% of its net assets in municipal securities that finance similar types of projects, such as education, healthcare, housing, industrial development, transportation, utilities, or pollution control. Economic, business, political, or other changes can affect all securities of a similar type.</p><p>All of the municipal securities in which the Fund invests are rated investment grade (BBB- or higher) at the time of purchase by a nationally recognized statistical rating service such as Standard and Poor's Ratings Services or Moody's Investors Service, Inc. or are of comparable quality as determined by the Fund's investment manager. If, subsequent to the purchase of a municipal security, the rating of a municipal security falls below investment grade, the Fund will not be required to dispose of the security.</p><p>Under normal circumstances, the Fund will maintain an average stated maturity at between eight and twenty-two years.</p><p>During unusual market or other conditions, the Fund may temporarily depart from its investment objective and invest up to 100% of its assets in short-term U.S. Government obligations, cash, and cash equivalents. During such times, the Fund may be unable to pursue its investment objective. In addition, these short-term investments may be taxable.</p><p>The Fund does not buy securities on margin, sell securities short, use commodities or futures contracts, or use derivative securities of any kind.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]19false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]20false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p><b><i>As with all mutual funds, there is the risk that you could lose money through your investment in the Fund. Many factors affect the Fund's net asset value and performance. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</i></b></p><p><b><i>General risk.</i></b> There is no assurance that the Fund will meet its investment objective. The Fund's share price, and the value of your investment, may change. When the value of the Fund's investments goes down, so does its share price. Similarly, when the value of the Fund's investments goes up, its share price does as well. Since the value of the Fund's shares can go up or down, it is possible to lose money by investing in the Fund.</p><p><b><i>Non-diversified fund.</i></b> Because the Fund is non-diversified, it may invest a relatively high percentage of its assets in a limited number of issuers; therefore its investment return is more likely to be impacted by changes in the market value and returns of any one issuer.</p><p><b><i>Municipal volatility risk.</i></b> The municipal market can be significantly affected by a number of factors, including adverse tax, legislative or political changes, changes in interest rates, general economic and market conditions, and the financial condition of the issuers of municipal securities.</p><p><b><i>Single-state fund.</i></b> Because the Fund focuses its investments in the municipal securities of Montana, adverse economic, political, or regulatory occurrences in Montana will have a greater impact on investment returns than would be the case for a municipal securities fund investing nationally. Montana's economy is based primarily on agriculture, tourism, energy, mining, and the processing of minerals and agricultural/forest products. Specific issues may arise pertaining to these sectors that may have an impact on the ability of local municipal securities issuers to meet their obligations.</p><p><b><i>Interest rate risk.</i></b> When interest rates rise, debt security prices fall. When interest rates fall, debt security prices go up. Generally, interest rates rise during times of inflation or a growing economy, and fall during an economic slowdown or recession.</p><p><b><i>Income risk.</i></b> The income from the Fund's portfolio may decline because of falling market interest rates. This can result when the Fund invests the proceeds from new share sales, or from matured or called bonds, at market rates that are below the portfolio's current earnings rate.</p><p><b><i>Maturity risk.</i></b> Generally, longer-term securities are more susceptible to changes in value as a result of interest-rate changes than are shorter-term securities.</p><p><b><i>Credit risk.</i></b> Credit risk is the possibility that an issuer will be unable to make interest payments or repay principal. Changes in an issuer's financial strength or in a security's credit rating may affect its value. Securities supported by insurance or other credit enhancements have the credit risk of the entity providing the insurance or other credit support. Changes in the credit quality of the insurer or other credit provider could affect the value of the security and the Fund's share price. Not all securities are rated. In the event that rating agencies assign different ratings to the same security, the Fund's investment manager will determine which rating it believes best reflects the security's quality and risk at that time. Credit risks associated with certain particular classifications of municipal securities include:</p><p><b><i>General Obligation Bonds</i></b>&#8212;Timely payments depend on the issuer's credit quality, ability to raise tax revenues, and ability to maintain an adequate tax base.</p><p><b><i>Revenue Bonds</i></b>&#8212;Payments depend on the money earned by the particular facility or class of facilities, or the amount of revenues derived from another source.</p><p><b><i>Private Activity Bonds</i></b>&#8212;Municipalities and other public authorities issue private activity bonds to finance development of facilities for use by a private enterprise. The private enterprise pays the principal and interest on the bond, and the issuer does not pledge its full faith, credit, and taxing power for repayment.</p><p><b><i>Municipal insurance risk.</i></b> The Fund's investments may include investments in insured municipal securities. Municipal security insurance does not guarantee the value of either individual municipal securities or of shares of the Fund. In addition, a municipal security insurance policy generally will not cover: (i) repayment of a municipal security before maturity (redemption), (ii) prepayment or payment of an acceleration premium (except for a mandatory sinking fund redemption) or any other provision of a bond indenture that advances the maturity of the bond or (iii) nonpayment of principal or interest caused by negligence or bankruptcy of the paying agent. A mandatory sinking fund redemption may be a provision of a municipal security issue whereby part of the municipal security issue may be retired before maturity. Adverse developments in the bond insurance industry may negatively affect the value of the Fund's insured municipal securities (if any) and the Fund. Because a significant portion of the municipal securities issued and outstanding are insured by a small number of insurance companies, an event involving one or more of these insurance companies could have a significant adverse effect on the value of the securities insured by that insurance company and on the municipal markets as a whole. The value of a municipal security will be affected by the credit standing of its insurer. If the credit quality of an insurer is downgraded, the rating on a municipal security insured by such insurer may also be downgraded. This may, in turn, sharply reduce and in some cases eliminate the value provided by insurance. Moreover, having multiple securities insured by the same insurer will increase the adverse effects on the Fund that are likely to result from a downgrading of, or a default by, such insurer.</p><p><b><i>Call risk.</i></b> Call risk is the likelihood that a security will be prepaid (or "called") before maturity. An issuer is more likely to call its bonds when interest rates are falling, because the issuer can issue new bonds with lower interest payments. If a bond is called, the Fund may have to replace it with a lower-yielding security.</p><p><b><i>Extension risk.</i></b> Extension risk is the risk that an issuer will exercise its right to pay principal on an obligation held by the Fund later than expected. This may happen during a period of rising interest rates. Under these circumstances, the value of the obligation will decrease and the Fund will suffer from the inability to invest in higher yielding securities.</p><p><b><i>Portfolio strategy.</i></b> The investment manager's skill in choosing appropriate investments for the Fund will determine in part the Fund's ability to achieve its investment objective.</p><p><b><i>Inflation risk.</i></b> There is a possibility that the rising prices of goods and services may have the effect of offsetting a Fund's real return. This is likely to have a greater impact on the returns of bond funds and money market funds, which historically have had more modest returns in comparison to equity funds. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions.</p><p><b><i>Tax risk.</i></b> Income from municipal securities held by the Fund could be declared taxable because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service or state tax authorities, or noncompliant conduct of a bond issuer. In addition, a portion of the Fund's otherwise exempt-interest dividends may be taxable to those shareholders subject to the federal alternative minimum tax.</p><p><b><i>Municipal sector risk.</i></b> The Fund may invest more than 25% of its total assets in municipal securities that finance, or pay interest from the revenues of, similar projects that tend to be impacted the same or similar ways by economic, business, or political developments, which would increase credit risk. For example, legislation on the financing of a project or a declining economic need for the project would likely affect all similar projects.</p><p><b><i>Risks of health care revenue bonds.</i></b> The Fund may invest in health care revenue bonds. The health care sector is subject to regulatory action by a number of private and governmental agencies, including federal, state, and local governmental agencies. A major source of revenues for the health care sector is payments from the Medicare and Medicaid programs. As a result, the sector is sensitive to legislative changes and reductions in governmental spending for such programs. Numerous other factors may affect the sector, such as general economic conditions; demand for services; expenses (including malpractice insurance premiums); and competition among health care providers.</p><p><b><i>Risks of educational revenue bonds.</i></b> The Fund may invest in educational revenue bonds. These include municipal securities that are obligations of issuers which are, or which govern the operation of, schools, colleges, and universities and whose revenues are derived mainly from ad valorem taxes, or for higher education systems, from tuition, dormitory revenues, grants, and endowments. Litigation or legislation pertaining to ad valorem taxes may affect sources of funds available for the payment of school bonds. College and university obligations may be affected by the possible inability to raise tuitions and fees sufficiently to cover increased operating costs, the uncertainty of continued receipt of Federal grants and state funding, and new government or legislation or regulations which may adversely affect the revenues or costs of such issuers. In addition, student loan revenue bonds, which are generally offered by state (or substate) authorities or commissions and backed by pools of student loans, may be affected by numerous factors, including the rate of student loan defaults, seasoning of the loan portfolio, student repayment deferral periods of forbearance, potential changes in federal legislation, and state guarantee agency reimbursement.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]21false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fund PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]22false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>The following bar chart and table provide some indication of the risks of investing in the Fund. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available at www.integrityvikingfunds.com or by calling 800-276-1262.</p><p>The bar chart below shows the variability of the Fund's performance from year to year. The bar chart and highest/lowest quarterly returns that follow do not reflect sales charges, and if these charges were reflected, the returns would be less than those shown.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]23false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Total Annual Return per Calendar Year (bar chart)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]24false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalseBarChart1.jpg<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForMontana row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000003821_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForMontanafalsefalse0200500 - Schedule - Annual Total Returns (Bar Chart)truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for MontanaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04480.0448falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04480.0448falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09900.0990falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09900.0990falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04450.0445falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04450.0445falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04050.0405falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04050.0405falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01960.0196falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01960.0196falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04150.0415falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04150.0415falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02960.0296falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02960.0296falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.0466-0.0466falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0466-0.0466falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.11970.1197falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.11970.1197falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01930.0193falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01930.0193falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]25false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00During the ten-year period shown in the bar chart, the highest return for a quarter was 6.39% (quarter ended September 30, 2009) and the lowest return for a quarter was -4.60% (quarter ended December 31, 2010).falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]26false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The table below shows the Fund's average annual returns for 1, 5, and 10 years, and since inception, and how they compare with those of a broad measure of market performance. The return information has been restated to reflect current sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts ("IRAs").falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative27false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average Annual Total Returns (for the periods ended December 31, 2010)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. 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This tag is used when this is reflected in a footnote.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 5 -Subsection b falsefalseIndex No Deduction for Fees, Expenses, Taxes [Text]falseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0187-0.0187falsefalsefalsetruefalse2truetruetrue-0.0187-0.0187falsefalsefalsetruefalse3truetruetrue-0.0099-0.0099falsefalsefalsetruefalse4truetruetrue0.02370.0237falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 YearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition 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-Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 YearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnSinceInceptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03660.0366falsefalsefalsetruefalse2truetruetrue0.03650.0365falsefalsefalsetruefalse3truetruetrue0.03730.0373falsefalsefalsetruefalse4truetruetrue0.05090.0509falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseSince InceptionfalseUSDfalsefalse$6falseColumnprimaryElement*9false0rr_AverageAnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse001999-08-03falsefalsetruetruefalse2falsetruefalse001999-08-03falsefalsetruetruefalse3falsetruefalse001999-08-03falsefalsetruetruefalse4falsetruefalse001999-08-03falsefalsetruetruefalseOtherxbrli:dateItemTypedateReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 4 -Subsection b falsefalseInception DatefalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn Before Taxesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_ReturnBeforeTaxesMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for MontanaReturn Before TaxesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0187-0.0187falsefalsefalsetruefalse3truetruetrue0.02350.0235falsefalsefalsetruefalse4truetruetrue0.03640.0364falsefalsefalsetruefalse5truetruetrue0.03660.0366falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn Before Taxes2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributionsrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for MontanaReturn After Taxes On DistributionsStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0187-0.0187falsefalsefalsetruefalse3truetruetrue0.02350.0235falsefalsefalsetruefalse4truetruetrue0.03630.0363falsefalsefalsetruefalse5truetruetrue0.03650.0365falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributions and Sale of Fund Sharesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsAndSalesMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for MontanaReturn After Taxes On Distributions and Sale of Fund SharesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0099-0.0099falsefalsefalsetruefalse3truetruetrue0.02580.0258falsefalsefalsetruefalse4truetruetrue0.03710.0371falsefalsefalsetruefalse5truetruetrue0.03730.0373falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions and Sale of Fund Shares4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for Montanadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000003821Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseBarclays Capital Municipal Bond Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_BarclaysCapitalMunicipalBondIndexMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for MontanaBarclays Capital Municipal Bond IndexStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(reflects no deduction for fees, expenses or taxes)(reflects no deduction for fees, expenses or taxes)falsefalsefalsetruefalse2truetruetrue0.02370.0237falsefalsefalsetruefalse3truetruetrue0.04090.0409falsefalsefalsetruefalse4truetruetrue0.04840.0484falsefalsefalsetruefalse5truetruetrue0.05090.0509falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseBarclays Capital Municipal Bond Index64Average Annual Total Returns Viking Tax-Free Fund for MontanaUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]29false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://integrityvikingfunds.com/role/riskreturnsummary1falsefalsefalse00Viking Tax-Free Fund for North DakotaViking Tax-Free Fund for North Dakotafalsefalsefalsefalsefalse2falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : Viking Tax-Free Fund for North Dakota 5/1/2010 - 4/30/2011 USD ($) $TwelveMonthsEnded_30Apr2011_S000026083_Memberhttp://www.sec.gov/CIK0001082744duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsevmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseViking Tax-Free Fund for North Dakota31false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00VIKING TAX-FREE FUND FOR NORTH DAKOTA&#8212;SUMMARYfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]33false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The Fund seeks the highest level of current income that is exempt from federal and North Dakota personal income taxes and is consistent with preservation of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]34false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and Expenses of the FundfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. 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 may indicate higher transaction costs. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]35false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This 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 with respect to purchases of shares of the Fund if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund or in other funds in the Integrity/Viking family of funds. More information about these and other discounts is available from your financial professional and in "Your Account" on page 23 of the Fund's prospectus and "Buying and Selling Shares" on page 30 of the Fund's statement of additional information.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]36false0rr_ShareholderFeesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Shareholder Fees (fees paid directly from your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subsection table falsefalseShareholder Fees Caption [Text]37false0rr_ShareholderFeesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/ShareholderFeesVikingTaxFreeFundForNorthDakotafalsefalse0200101 - Schedule - Shareholder Feestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for North DakotaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03750.0375falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricetruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.03750.0375falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)2falseRowprimaryElement*5false0rr_MaximumDeferredSalesChargeOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01500.0150falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)0rr_MaximumDeferredSalesChargeOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01500.0150falsefalsefalsetruefalseOthernanafalsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)3falseRowprimaryElement*6false0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Sales Charge (Load) Imposed on Reinvested Dividends[and other Distributions] (as a percentage of ____)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 3 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends4falseRowprimaryElement*7false0rr_RedemptionFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonPositivePure4Typepure"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph b -Subsection instructions falsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)0rr_RedemptionFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)5falseRowprimaryElement*8false0rr_ExchangeFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureExchange Fee includes the maximum fee charged for any exchange or transfer of interest from the Fund to another fund. The Fund may include in a footnote to the table, if applicable, a tabular presentation of the range of exchange fees or a narrative explanation of the fees.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph c -Subsection instructions falsefalseExchange Fee0rr_ExchangeFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseExchange Fee15Shareholder Fees UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ShareholderFeesData.No authoritative reference available.falsefalseShareholder Fees [Table]38false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]39false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingTaxFreeFundForNorthDakotafalsefalse0200201 - Schedule - Annual Fund Operating Expensestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for North DakotaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00500.0050falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement Fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00500.0050falsefalsefalsetruefalseOthernanafalsefalseManagement Fees2falseRowprimaryElement*5false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00250.0025falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and Service (12b-1) Fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and Service (12b-1) Fees3falseRowprimaryElement*6false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00670.0067falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther Expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00670.0067falsefalsefalsetruefalseOthernanafalsefalseOther Expenses4falseRowprimaryElement*7false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01420.0142falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal Annual Fund Operating Expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01420.0142falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses5falseRowprimaryElement*8false0rr_FeeWaiverOrReimbursementOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0035-0.0035[1]falsefalsefalsetruefalseOtherrr:NonPositivePure4TypepureTotal Annual Fund Operating Expenses. If there were expense reimbursement or fee waiver arrangements that reduced any Fund operating expenses and will continue to reduce them for no less than one year from the effective date of the Fund's registration statement, a Fund may add two captions to the table one caption showing the amount of the expense reimbursement or fee waiver, and a second caption showing the Fund's net expenses after subtracting the fee reimbursement or expense waiver from the total fund operating expenses. The Fund should place these additional captions directly below the "Total Annual Fund Operating Expenses" caption of the table and should use appropriate descriptive captions, such as "Fee Waiver [and/or Expense Reimbursement]" and "Total Annual Fund Operating Expenses After Fee Waiver [and/or Expense Reimbursement]," respectively. If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseFee Waivers and Expense Reimbursements0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[1]1truetruetrue-0.0035-0.0035falsefalsefalsetruefalseOthernanafalsefalseFee Waivers and Expense Reimbursements6falseRowprimaryElement*9false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01070.0107falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01070.0107falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements1The Fund's investment adviser has contractually agreed to waive fees and reimburse expenses from April 30, 2011 through April 29, 2012 so that Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements (excluding taxes, brokerage fees, commissions, extraordinary and non-recurring expenses, and Acquired Fund Fees and Expenses) do not exceed 1.07% of average daily net assets. If the Fund incurred extraordinary or non-recurring expenses, Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements would be higher than what is shown in the table above. This expense limitation agreement may only be terminated or modified prior to April 29, 2012 with the approval of the Fund's Board of Trustees.16Annual Fund Operating Expenses UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]40false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]41false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This Example is intended to help you compare the cost of investing in the Fund with the costs 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:falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]42false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>truehttp://integrityvikingfunds.com/role/ExpenseExampleVikingTaxFreeFundForNorthDakotafalsefalse0200301 - Schedule - Expense Example {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue481481falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 YearfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue782782falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 YearsfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11151115falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 YearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue21032103falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 YearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for North DakotaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue481481falsefalsefalsetruefalse2truefalsetrue782782falsefalsefalsetruefalse3truefalsetrue11151115falsefalsefalsetruefalse4truefalsetrue21032103falsefalsefalsetruefalseOthernanafalsefalseViking Tax-Free Fund for North Dakota41Expense Example (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]43false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio TurnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]44false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The 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 Fund 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 29.47% of the average value of its portfolio.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]45false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment StrategiesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]46false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>To pursue its objective, the Fund normally invests:</p><p>&#8226; at least 80% of its net assets (including any borrowings for investment purposes) in municipal securities that pay interest free from federal income taxes, including the federal alternative minimum tax;</p><p>&#8226; at least 80% of its net assets (including any borrowings for investment purposes) in municipal securities that pay interest free from North Dakota personal income taxes, although the Fund tries to invest all of its assets in these securities.</p><p>Municipal bonds are debt securities issued by or on behalf of states, territories, and possessions of the United States and their political subdivisions, agencies, authorities, and instrumentalities. The two general classifications of municipal bonds are "general obligation" and "revenue" bonds. General obligation bonds are secured by the issuer's pledge of its faith, credit, and taxing power for the payment of principal and interest. Revenue bonds are payable only from the revenues derived from a particular facility or class of facilities or, in some cases, from the proceeds of a special excise tax or other specific revenue source.</p><p>The investment manager actively manages the Fund's portfolio by selecting securities that it believes will provide the best balance between risk and return within the Fund's range of allowable investments. The investment manager will consider selling a security with deteriorating credit or limited upside potential compared to other available bonds.</p><p>The Fund may invest up to 30% of its net assets in U.S. territorial obligations (including qualifying obligations of Puerto Rico, the U.S. Virgin Islands, and Guam), the interest on which is exempt from federal and North Dakota personal income taxes. The Fund may invest up to 20% of its net assets in private activity bonds (which are revenue bonds that finance privately operated facilities), the interest on which is a tax preference item for purposes of the federal alternative minimum tax.</p><p>The Fund may invest more than 25% of its net assets in municipal securities that finance similar types of projects, such as education, healthcare, housing, industrial development, transportation, utilities, or pollution control. Economic, business, political, or other changes can affect all securities of a similar type.</p><p>All of the municipal securities in which the Fund invests are rated investment grade (BBB- or higher) at the time of purchase by a nationally recognized statistical rating service such as Standard and Poor's Ratings Services or Moody's Investors Service, Inc. or are of comparable quality as determined by the Fund's investment manager. If, subsequent to the purchase of a municipal security the rating of a municipal security falls below investment grade, the Fund will not be required to dispose of the security.</p><p>Under normal circumstances, the Fund will maintain an average stated maturity at between eight and twenty-two years.</p><p>During unusual market or other conditions, the Fund may temporarily depart from its investment objective and invest up to 100% of its assets in short-term U.S. Government obligations, cash, and cash equivalents. During such times, the Fund may be unable to pursue its investment objective. In addition, these short-term investments may be taxable.</p><p>The Fund does not buy securities on margin, sell securities short, use commodities or futures contracts, or use derivative securities of any kind.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]47false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]48false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p><b><i>As with all mutual funds, there is the risk that you could lose money through your investment in the Fund. Many factors affect the Fund's net asset value and performance. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</i></b></p> <p><b><i>General risk.</i></b> There is no assurance that the Fund will meet its investment objective. The Fund's share price, and the value of your investment, may change. When the value of the Fund's investments goes down, so does its share price. Similarly, when the value of the Fund's investments goes up, its share price does as well. Since the value of the Fund's shares can go up or down, it is possible to lose money by investing in the Fund.</p> <p><b><i>Non-diversified fund.</i></b> Because the Fund is non-diversified, it may invest a relatively high percentage of its assets in a limited number of issuers; therefore its investment return is more likely to be impacted by changes in the market value and returns of any one issuer.</p> <p><b><i>Municipal volatility risk.</i></b> The municipal market can be significantly affected by a number of factors, including adverse tax, legislative or political changes, changes in interest rates, general economic and market conditions, and the financial condition of the issuers of municipal securities.</p> <p><b><i>Single-state fund.</i></b> Because the Fund focuses its investments in the municipal securities of North Dakota, adverse economic, political or regulatory occurrences in North Dakota will have a greater impact on investment returns than would be the case for a municipal securities fund investing nationally. North Dakota's economy is based primarily on agriculture, mining, and energy. Specific issues may arise pertaining to these sectors that may have an impact on the ability of local municipal securities issuers to meet their obligations.</p> <p><b><i>Interest rate risk.</i></b> When interest rates rise, debt security prices fall. When interest rates fall, debt security prices go up. Generally, interest rates rise during times of inflation or a growing economy, and fall during an economic slowdown or recession.</p> <p><b><i>Income risk.</i></b> The income from the Fund's portfolio may decline because of falling market interest rates. This can result when the Fund invests the proceeds from new share sales, or from matured or called bonds, at market rates that are below the portfolio's current earnings rate.</p> <p><b><i>Maturity risk.</i></b> Generally, longer-term securities are more susceptible to changes in value as a result of interest-rate changes than are shorter-term securities.</p> <p><b><i>Credit risk.</i></b> Credit risk is the possibility that an issuer will be unable to make interest payments or repay principal. Changes in an issuer's financial strength or in a security's credit rating may affect its value. Securities supported by insurance or other credit enhancements have the credit risk of the entity providing the insurance or other credit support. Changes in the credit quality of the insurer or other credit provider could affect the value of the security and the Fund's share price. Not all securities are rated. In the event that rating agencies assign different ratings to the same security, the Fund's investment manager will determine which rating it believes best reflects the security's quality and risk at that time. Credit risks associated with certain particular classifications of municipal securities include:</p> <p><b><i>General Obligation Bonds</i></b>&#8212;Timely payments depend on the issuer's credit quality, ability to raise tax revenues, and ability to maintain an adequate tax base.</p> <p><b><i>Revenue Bonds</i></b>&#8212;Payments depend on the money earned by the particular facility or class of facilities, or the amount of revenues derived from another source.</p> <p><b><i>Private Activity Bonds</i></b>&#8212;Municipalities and other public authorities issue private activity bonds to finance development of facilities for use by a private enterprise. The private enterprise pays the principal and interest on the bond, and the issuer does not pledge its full faith, credit, and taxing power for repayment.</p> <p><b><i>Municipal insurance risk.</i></b> The Fund's investments may include investments in insured municipal securities. Municipal security insurance does not guarantee the value of either individual municipal securities or of shares of the Fund. In addition, a municipal security insurance policy generally will not cover: (i) repayment of a municipal security before maturity (redemption), (ii) prepayment or payment of an acceleration premium (except for a mandatory sinking fund redemption) or any other provision of a bond indenture that advances the maturity of the bond or (iii) nonpayment of principal or interest caused by negligence or bankruptcy of the paying agent. A mandatory sinking fund redemption may be a provision of a municipal security issue whereby part of the municipal security issue may be retired before maturity. Adverse developments in the bond insurance industry may negatively affect the value of the Fund's insured municipal securities (if any) and the Fund. Because a significant portion of the municipal securities issued and outstanding are insured by a small number of insurance companies, an event involving one or more of these insurance companies could have a significant adverse effect on the value of the securities insured by that insurance company and on the municipal markets as a whole. The value of a municipal security will be affected by the credit standing of its insurer. If the credit quality of an insurer is downgraded, the rating on a municipal security insured by such insurer may also be downgraded. This may, in turn, sharply reduce and in some cases eliminate the value provided by insurance. Moreover, having multiple securities insured by the same insurer will increase the adverse effects on the Fund that are likely to result from a downgrading of, or a default by, such insurer.</p> <p><b><i>Call risk.</i></b> Call risk is the likelihood that a security will be prepaid (or "called") before maturity. An issuer is more likely to call its bonds when interest rates are falling, because the issuer can issue new bonds with lower interest payments. If a bond is called, the Fund may have to replace it with a lower-yielding security.</p> <p><b><i>Extension risk.</i></b> Extension risk is the risk that an issuer will exercise its right to pay principal on an obligation held by the Fund later than expected. This may happen during a period of rising interest rates. Under these circumstances, the value of the obligation will decrease and the Fund will suffer from the inability to invest in higher yielding securities.</p> <p><b><i>Portfolio strategy.</i></b> The investment manager's skill in choosing appropriate investments for the Fund will determine in part the Fund's ability to achieve its investment objective.</p> <p><b><i>Inflation risk.</i></b> There is a possibility that the rising prices of goods and services may have the effect of offsetting a Fund's real return. This is likely to have a greater impact on the returns of bond funds and money market funds, which historically have had more modest returns in comparison to equity funds. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions.</p> <p><b><i>Tax risk.</i></b> Income from municipal securities held by the Fund could be declared taxable because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service or state tax authorities, or noncompliant conduct of a bond issuer. In addition, a portion of the Fund's otherwise exempt-interest dividends may be taxable to those shareholders subject to the federal alternative minimum tax.</p> <p><b><i>Municipal sector risk.</i></b> The Fund may invest more than 25% of its total assets in municipal securities that finance, or pay interest from the revenues of, similar projects that tend to be impacted the same or similar ways by economic, business, or political developments, which would increase credit risk. For example, legislation on the financing of a project or a declining economic need for the project would likely affect all similar projects.</p> <p><b><i>Risks of health care revenue bonds.</i></b> The Fund may invest in health care revenue bonds. The health care sector is subject to regulatory action by a number of private and governmental agencies, including federal, state, and local governmental agencies. A major source of revenues for the health care sector is payments from the Medicare and Medicaid programs. As a result, the sector is sensitive to legislative changes and reductions in governmental spending for such programs. Numerous other factors may affect the sector, such as general economic conditions; demand for services; expenses (including malpractice insurance premiums); and competition among health care providers.</p> <p><b><i>Risks of educational revenue bonds.</i></b> The Fund may invest in educational revenue bonds. These include municipal securities that are obligations of issuers which are, or which govern the operation of, schools, colleges, and universities and whose revenues are derived mainly from ad valorem taxes, or for higher education systems, from tuition, dormitory revenues, grants, and endowments. Litigation or legislation pertaining to ad valorem taxes may affect sources of funds available for the payment of school bonds. College and university obligations may be affected by the possible inability to raise tuitions and fees sufficiently to cover increased operating costs, the uncertainty of continued receipt of Federal grants and state funding, and new government or legislation or regulations which may adversely affect the revenues or costs of such issuers. In addition, student loan revenue bonds, which are generally offered by state (or substate) authorities or commissions and backed by pools of student loans, may be affected by numerous factors, including the rate of student loan defaults, seasoning of the loan portfolio, student repayment deferral periods of forbearance, potential changes in federal legislation, and state guarantee agency reimbursement.</p> <p><b><i>Risks of electric utility revenue bonds.</i></b> The Fund may invest in electric utility revenue bonds. Risks associated with electric utility revenue bonds include: (a) the availability and costs of fuel; (b) the availability and costs of capital; (c) the effects of conservation on energy demand; (d) the effects of rapidly changing environmental, safety, and licensing requirements, and other federal, state, and local regulations; (e) timely and sufficient rate increases; and (f) opposition to nuclear power.</p> <p><b><i>Risks of gas utility revenue bonds.</i></b> The Fund may invest in gas utility revenue bonds. Gas utilities are subject to the risks of supply conditions and increased competition from other providers of utility services. In addition, gas utilities are affected by gas prices, which may be magnified to the extent that a gas company enters into long-term contracts for the purchase or sale of gas at fixed prices, since such prices may change significantly and to the disadvantage of the gas utility in the open market. Gas utilities are particularly susceptible to supply and demand imbalances due to unpredictable climate conditions and other factors and are subject to regulatory risks as well.</p> <p><b><i>Risks of water and sewer revenue bonds.</i></b> The Fund may invest in water and sewer revenue bonds. Issuers of water and sewer bonds face public resistance to rate increases, costly environmental litigation, and Federal environmental mandates. In addition, the lack of water supply due to insufficient rain, run-off, or snow pack may be a concern.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]49false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fund PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]50false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>The following bar chart and table provide some indication of the risks of investing in the Fund. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available at www.integrityvikingfunds.com or by calling 800-276-1262.</p> <p>The bar chart below shows the variability of the Fund's performance from year to year. The bar chart and highest/lowest quarterly returns that follow do not reflect sales charges, and if these charges were reflected, the returns would be less than those shown.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]51false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Total Annual Return per Calendar Year (bar chart)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]52false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalseBarChart2.jpg<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForNorthDakota row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026083_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingTaxFreeFundForNorthDakotafalsefalse0200501 - Schedule - Annual Total Returns (Bar Chart)truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Tax-Free Fund for North DakotaUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03260.0326falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03260.0326falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.10070.1007falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.10070.1007falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04600.0460falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04600.0460falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03760.0376falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03760.0376falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02240.0224falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02240.0224falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04770.0477falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04770.0477falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02770.0277falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02770.0277falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.0489-0.0489falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0489-0.0489falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13770.1377falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13770.1377falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01480.0148falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01480.0148falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]53false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00During the ten-year period shown in the bar chart, the highest return for a quarter was 6.38% (quarter ended September 30, 2009) and the lowest return for a quarter was -4.56% (quarter ended December 31, 2010).falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]54false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The table below shows the Fund's average annual returns for 1, 5, and 10 years, and since inception, and how they compare with those of a broad measure of market performance. The return information has been restated to reflect current sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts ("IRAs").falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative55false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average Annual Total Returns (for the periods ended December 31, 2010)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. 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This tag is used when this is reflected in a footnote.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 5 -Subsection b falsefalseIndex No Deduction for Fees, Expenses, Taxes [Text]falseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0231-0.0231falsefalsefalsetruefalse2truetruetrue-0.0231-0.0231falsefalsefalsetruefalse3truetruetrue-0.0137-0.0137falsefalsefalsetruefalse4truetruetrue0.02370.0237falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 YearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition 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-Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 YearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnSinceInceptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03870.0387falsefalsefalsetruefalse2truetruetrue0.03870.0387falsefalsefalsetruefalse3truetruetrue0.03930.0393falsefalsefalsetruefalse4truetruetrue0.05090.0509falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseSince InceptionfalseUSDfalsefalse$6falseColumnprimaryElement*9false0rr_AverageAnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse001999-08-03falsefalsetruetruefalse2falsetruefalse001999-08-03falsefalsetruetruefalse3falsetruefalse001999-08-03falsefalsetruetruefalse4falsetruefalse001999-08-03falsefalsetruetruefalseOtherxbrli:dateItemTypedateReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 4 -Subsection b falsefalseInception DatefalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn Before Taxesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_ReturnBeforeTaxesMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for North DakotaReturn Before TaxesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0231-0.0231falsefalsefalsetruefalse3truetruetrue0.02610.0261falsefalsefalsetruefalse4truetruetrue0.03680.0368falsefalsefalsetruefalse5truetruetrue0.03870.0387falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn Before Taxes2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributionsrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for North DakotaReturn After Taxes On DistributionsStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0231-0.0231falsefalsefalsetruefalse3truetruetrue0.02610.0261falsefalsefalsetruefalse4truetruetrue0.03680.0368falsefalsefalsetruefalse5truetruetrue0.03870.0387falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributions and Sale of Fund Sharesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsAndSalesMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for North DakotaReturn After Taxes On Distributions and Sale of Fund SharesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0137-0.0137falsefalsefalsetruefalse3truetruetrue0.02800.0280falsefalsefalsetruefalse4truetruetrue0.03750.0375falsefalsefalsetruefalse5truetruetrue0.03930.0393falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions and Sale of Fund Shares4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Tax-Free Fund for North Dakotadei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026083Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseBarclays Capital Municipal Bond Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_BarclaysCapitalMunicipalBondIndexMemberrr_PerformanceMeasureAxisexplicitMemberViking Tax-Free Fund for North DakotaBarclays Capital Municipal Bond IndexStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(reflects no deduction for fees, expenses or taxes)(reflects no deduction for fees, expenses or taxes)falsefalsefalsetruefalse2truetruetrue0.02370.0237falsefalsefalsetruefalse3truetruetrue0.04090.0409falsefalsefalsetruefalse4truetruetrue0.04840.0484falsefalsefalsetruefalse5truetruetrue0.05090.0509falsefalsefalsetruefalse6falsetruefalse001999-08-031999-08-03falsefalsetruetruefalseOthernanafalsefalseBarclays Capital Municipal Bond Index64Average Annual Total Returns Viking Tax-Free Fund for North DakotaUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]57false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://integrityvikingfunds.com/role/riskreturnsummary1falsefalsefalse00Viking Small-Cap Value FundViking Small-Cap Value Fundfalsefalsefalsefalsefalse3falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : Viking Small-Cap Value Fund 5/1/2010 - 4/30/2011 USD ($) $TwelveMonthsEnded_30Apr2011_S000026085_Memberhttp://www.sec.gov/CIK0001082744duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsevmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseViking Small-Cap Value Fund59false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00VIKING SMALL-CAP VALUE FUND&#8212;SUMMARYfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]60false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Investment ObjectivefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]61false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The Fund seeks long-term total return and capital preservation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]62false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and Expenses of the FundfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. 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 may indicate higher transaction costs. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]63false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This 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 with respect to purchases of shares of the Fund if you and your family invest, or agree to invest in the future, at least $100,000 in the Fund or in other funds in the Integrity/Viking family of funds. More information about these and other discounts is available from your financial professional and in "Your Account" on page 23 of the Fund's prospectus and "Buying and Selling Shares" on page 30 of the Fund's statement of additional information.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]64false0rr_ShareholderFeesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Shareholder Fees (fees paid directly from your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subsection table falsefalseShareholder Fees Caption [Text]65false0rr_ShareholderFeesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ShareholderFeesVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/ShareholderFeesVikingSmallCapValueFundfalsefalse0200102 - Schedule - Shareholder Feestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Small-Cap Value FundUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.05000.0500falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricetruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.05000.0500falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)2falseRowprimaryElement*5false0rr_MaximumDeferredSalesChargeOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01000.0100falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)0rr_MaximumDeferredSalesChargeOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01000.0100falsefalsefalsetruefalseOthernanafalsefalseMaximum Deferred Sales Charge (Load) (as a percentage of the lesser of purchase price or redemption proceeds)3falseRowprimaryElement*6false0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureMaximum Sales Charge (Load) Imposed on Reinvested Dividends[and other Distributions] (as a percentage of ____)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 3 -Subsection table falsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends0rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseMaximum Sales Charge (Load) Imposed on Reinvested Dividends4falseRowprimaryElement*7false0rr_RedemptionFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonPositivePure4Typepure"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph b -Subsection instructions falsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)0rr_RedemptionFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseRedemption Fee (as a percentage of amount redeemed, if applicable)5falseRowprimaryElement*8false0rr_ExchangeFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureExchange Fee includes the maximum fee charged for any exchange or transfer of interest from the Fund to another fund. The Fund may include in a footnote to the table, if applicable, a tabular presentation of the range of exchange fees or a narrative explanation of the fees.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph c -Subsection instructions falsefalseExchange Fee0rr_ExchangeFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseExchange Fee15Shareholder Fees UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ShareholderFeesData.No authoritative reference available.falsefalseShareholder Fees [Table]66false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]67false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualFundOperatingExpensesVikingSmallCapValueFundfalsefalse0200202 - Schedule - Annual Fund Operating Expensestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Small-Cap Value FundUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01000.0100falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement Fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01000.0100falsefalsefalsetruefalseOthernanafalsefalseManagement Fees2falseRowprimaryElement*5false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00250.0025falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and Service (12b-1) Fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and Service (12b-1) Fees3falseRowprimaryElement*6false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01520.0152falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther Expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01520.0152falsefalsefalsetruefalseOthernanafalsefalseOther Expenses4falseRowprimaryElement*7false0rr_AcquiredFundFeesAndExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00010.0001[1]falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseAcquired Fund Fees and Expenses0rr_AcquiredFundFeesAndExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[1]1truetruetrue0.00010.0001falsefalsefalsetruefalseOthernanafalsefalseAcquired Fund Fees and Expenses5falseRowprimaryElement*8false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.02780.0278falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal Annual Fund Operating Expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.02780.0278falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses6falseRowprimaryElement*9false0rr_FeeWaiverOrReimbursementOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0112-0.0112[2]falsefalsefalsetruefalseOtherrr:NonPositivePure4TypepureTotal Annual Fund Operating Expenses. If there were expense reimbursement or fee waiver arrangements that reduced any Fund operating expenses and will continue to reduce them for no less than one year from the effective date of the Fund's registration statement, a Fund may add two captions to the table one caption showing the amount of the expense reimbursement or fee waiver, and a second caption showing the Fund's net expenses after subtracting the fee reimbursement or expense waiver from the total fund operating expenses. The Fund should place these additional captions directly below the "Total Annual Fund Operating Expenses" caption of the table and should use appropriate descriptive captions, such as "Fee Waiver [and/or Expense Reimbursement]" and "Total Annual Fund Operating Expenses After Fee Waiver [and/or Expense Reimbursement]," respectively. If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseFee Waivers and Expense Reimbursements0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[2]1truetruetrue-0.0112-0.0112falsefalsefalsetruefalseOthernanafalsefalseFee Waivers and Expense Reimbursements7falseRowprimaryElement*10false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01660.0166falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01660.0166falsefalsefalsetruefalseOthernanafalsefalseTotal Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements1Acquired Fund Fees and Expenses are the indirect costs of investing in other investment companies. The Total Annual Fund Operating Expenses do not correlate with the ratio of expenses to average net assets in the Fund's financial highlights, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.2The Fund's investment adviser has contractually agreed to waive fees and reimburse expenses from April 30, 2011 through April 29, 2012 so that Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements (excluding taxes, brokerage fees, commissions, extraordinary and non-recurring expenses, and Acquired Fund Fees and Expenses) do not exceed 1.65% of average daily net assets. If the Fund incurred extraordinary or non-recurring expenses, Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements would be higher than what is shown in the table above. This expense limitation agreement may only be terminated or modified prior to April 29, 2012 with the approval of the Fund's Board of Trustees.17Annual Fund Operating Expenses UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]68false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]69false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This Example is intended to help you compare the cost of investing in the Fund with the costs 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:falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]70false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/ExpenseExampleVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>truehttp://integrityvikingfunds.com/role/ExpenseExampleVikingSmallCapValueFundfalsefalse0200302 - Schedule - Expense Example {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue662662falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 YearfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue12441244falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 YearsfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue18871887falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 YearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue37963796falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 YearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Small-Cap Value FundUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue662662falsefalsefalsetruefalse2truefalsetrue12441244falsefalsefalsetruefalse3truefalsetrue18871887falsefalsefalsetruefalse4truefalsetrue37963796falsefalsefalsetruefalseOthernanafalsefalseViking Small-Cap Value Fund41Expense Example (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]71false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio TurnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]72false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The 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 Fund 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 42.94% of the average value of its portfolio.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]73false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment StrategiesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]74false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>To pursue its objective, the Fund normally invests at least 80% of its net assets (including any borrowing for investment purposes) in equity securities of small-capitalization companies. The Fund currently defines small-cap companies as companies with total market capitalization of no more than $3 billion at the time the Fund first invests in them. The Fund may continue to hold or add to a position in a company&#8217;s securities after it has grown beyond $3 billion.</p><p>The Fund invests primarily in the equity securities of U.S. companies that are among the leaders in their respective industries. Equity securities generally entitle the holder to participate in a company&#8217;s operating results. These include common stocks and preferred stocks. The Fund&#8217;s Portfolio Management Team ("Team") invests the Fund&#8217;s assets by pursuing a value-oriented strategy. The strategy begins with a screening process that seeks to identify companies whose stocks sell at below average price-to-earnings (P/E) and price-to-cash flow (P/CF) multiples but whose earnings growth rates are above average. Favored are high quality companies, those with dominant and growing business franchises, strong balance sheets, and predictable cash flows. The Team attempts to discern situations where intrinsic asset values are not widely recognized. Rigorous fundamental analysis, from both a quantitative and qualitative standpoint, is applied to all investment candidates. Although the Team employs a disciplined "bottom-up" approach to identify undervalued stocks, it is sensitive to emerging trends in different economic sectors. The Team will consider selling a security if its valuation target is achieved or if its business fundamentals have deteriorated.</p><p>The Fund may invest up to 20% of its net assets in sponsored American Depositary Receipts ("ADRs"). ADRs are typically issued by a U.S. bank or trust company and evidence ownership of underlying securities issued by a foreign corporation.</p><p>During unusual market or other conditions, the Fund may temporarily depart from its investment objective and invest up to 100% of its assets in short-term U.S. Government obligations, cash, and cash equivalents. During such times, the Fund may be unable to pursue its investment objective.</p><p>The Fund does not buy securities on margin, sell securities short, use commodities or futures contracts, or use derivative securities of any kind.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]75false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]76false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p><b><i>As with all mutual funds, there is the risk that you could lose money through your investment in the Fund. Many factors affect the Fund&#8217;s net asset value and performance. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</i></b></p><p><b><i>General risk.</i></b> There is no assurance that the Fund will meet its investment objective. The Fund&#8217;s share price, and the value of your investment, may change. When the value of the Fund&#8217;s investments goes down, so does its share price. Similarly, when the value of the Fund&#8217;s investments goes up, its share price does as well. Since the value of the Fund&#8217;s shares can go up or down, it is possible to lose money by investing in the Fund.</p><p><b><i>Stock market volatility.</i></b> Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market or economic developments. Different parts of the market can react differently to these developments.</p><p><b><i>Small-cap stock risk.</i></b> Small company stocks may present greater opportunities for capital appreciation, but tend to be more volatile than stocks of larger companies, in part, because small companies tend to be less established than larger companies and more vulnerable to competitive challenges and bad economic news.</p><p><b><i>Securities of foreign issuers.</i></b> Although they may add diversification, investments in U.S. dollar-denominated securities of foreign issuers, such as ADRs, can be riskier, due to political instability, less government supervision, less regulation, less publicly available information and lack of uniform accounting standards.</p><p><b><i>Issuer-specific changes.</i></b> The value of an individual security can be more volatile than the market as a whole and can perform differently than the value of the market as a whole.</p><p><b><i>Portfolio strategy.</i></b> The Team&#8217;s skill in choosing appropriate investments for the Fund will determine in part the Fund&#8217;s ability to achieve its investment objective. With a value approach, there is also the risk that the stocks may remain undervalued during a given period. This may happen because value stocks as a category lose favor with investors compared to growth stocks.</p><p><b><i>Common stock risk.</i></b> Investments in common stocks and other equity securities are particularly subject to the risk of changing economic, stock market, industry, and company conditions and the risks inherent in the portfolio managers&#8217; ability to anticipate changes that can adversely affect the value of the Fund&#8217;s holdings.</p><p><b><i>Preferred stock risk.</i></b> Preferred stocks are subject to the risks associated with other types of equity securities, as well as additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]77false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fund PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]78false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>The following bar chart and table provide some indication of the risks of investing in the Fund. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available at www.integrityvikingfunds.com or by calling 800-276-1262.</p><p>The bar chart below shows the variability of the Fund's performance from year to year. The bar chart and highest/lowest quarterly returns that follow do not reflect sales charges, and if these charges were reflected, the returns would be less than those shown.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]79false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Total Annual Return per Calendar Year (bar chart)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]80false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalseBarChart3.jpg<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsehttp://integrityvikingfunds.com/role/AnnualTotalReturnsBarChartVikingSmallCapValueFundfalsefalse0200502 - Schedule - Annual Total Returns (Bar Chart)truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberViking Small-Cap Value FundUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.0887-0.0887falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0887-0.0887falsefalsefalsetruefalseOthernanafalsefalse20022falseRowprimaryElement*5false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.32940.3294falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.32940.3294falsefalsefalsetruefalseOthernanafalsefalse20033falseRowprimaryElement*6false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.17860.1786falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.17860.1786falsefalsefalsetruefalseOthernanafalsefalse20044falseRowprimaryElement*7false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04180.0418falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04180.0418falsefalsefalsetruefalseOthernanafalsefalse20055falseRowprimaryElement*8false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.14020.1402falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14020.1402falsefalsefalsetruefalseOthernanafalsefalse20066falseRowprimaryElement*9false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02410.0241falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02410.0241falsefalsefalsetruefalseOthernanafalsefalse20077falseRowprimaryElement*10false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2712-0.2712falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2712-0.2712falsefalsefalsetruefalseOthernanafalsefalse20088falseRowprimaryElement*11false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.23820.2382falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.23820.2382falsefalsefalsetruefalseOthernanafalsefalse20099falseRowprimaryElement*12false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.17760.1776falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.17760.1776falsefalsefalsetruefalseOthernanafalsefalse201019Annual Total Returns (Bar Chart) UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]81false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00During the nine-year period shown in the bar chart, the highest return for a quarter was 18.67% (quarter ended June 30, 2009) and the lowest return for a quarter was -22.97% (quarter ended December 31, 2008).falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]82false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The table below shows the Fund's average annual returns for 1 and 5 years, and since inception, and how they compare with those of a broad measure of market performance. The return information has been restated to reflect current sales charges which became effective as of April 30, 2011. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts ("IRAs").falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative83false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average Annual Total Returns (for the periods ended December 31, 2010)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption84false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AverageAnnualTotalReturnsVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>falsefalse<div>&lt;div style="display: none"&gt;~ http://integrityvikingfunds.com/role/AverageAnnualTotalReturnsVikingSmallCapValueFund row period compact * row primary compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row dei_DocumentInformationDocumentAxis compact vmf1082744 _S000026085_Member * ~ Rows and columns are reversed here due to transposition&lt;/div&gt;</div>truehttp://integrityvikingfunds.com/role/AverageAnnualTotalReturnsVikingSmallCapValueFundfalsefalse0200602 - Schedule - Average Annual Total Returns {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00(reflects no deduction for fees, expenses or taxes)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". This tag is used when this is reflected in a footnote.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 5 -Subsection b falsefalseIndex No Deduction for Fees, Expenses, Taxes [Text]falseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.11860.1186falsefalsefalsetruefalse2truetruetrue0.11820.1182falsefalsefalsetruefalse3truetruetrue0.10060.1006falsefalsefalsetruefalse4truetruetrue0.24500.2450falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 YearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03350.0335falsefalsefalsetruefalse2truetruetrue0.02950.0295falsefalsefalsetruefalse3truetruetrue0.02840.0284falsefalsefalsetruefalse4truetruetrue0.03520.0352falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse5 YearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_AverageAnnualReturnSinceInceptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.06240.0624falsefalsefalsetruefalse2truetruetrue0.05920.0592falsefalsefalsetruefalse3truetruetrue0.05450.0545falsefalsefalsetruefalse4truetruetrue0.08100.0810falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseSince InceptionfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse002001-05-03falsefalsetruetruefalse2falsetruefalse002001-05-03falsefalsetruetruefalse3falsetruefalse002001-05-03falsefalsetruetruefalse4falsetruefalse002001-05-03falsefalsetruetruefalseOtherxbrli:dateItemTypedateReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 4 -Subsection b falsefalseInception DatefalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn Before Taxesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_ReturnBeforeTaxesMemberrr_PerformanceMeasureAxisexplicitMemberViking Small-Cap Value FundReturn Before TaxesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.11860.1186falsefalsefalsetruefalse3truetruetrue0.03350.0335falsefalsefalsetruefalse4truetruetrue0.06240.0624falsefalsefalsetruefalse5falsetruefalse002001-05-032001-05-03falsefalsetruetruefalseOthernanafalsefalseReturn Before Taxes2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributionsrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsMemberrr_PerformanceMeasureAxisexplicitMemberViking Small-Cap Value FundReturn After Taxes On DistributionsStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.11820.1182falsefalsefalsetruefalse3truetruetrue0.02950.0295falsefalsefalsetruefalse4truetruetrue0.05920.0592falsefalsefalsetruefalse5falsetruefalse002001-05-032001-05-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseReturn After Taxes On Distributions and Sale of Fund Sharesrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsAndSalesMemberrr_PerformanceMeasureAxisexplicitMemberViking Small-Cap Value FundReturn After Taxes On Distributions and Sale of Fund SharesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.10060.1006falsefalsefalsetruefalse3truetruetrue0.02840.0284falsefalsefalsetruefalse4truetruetrue0.05450.0545falsefalsefalsetruefalse5falsetruefalse002001-05-032001-05-03falsefalsetruetruefalseOthernanafalsefalseReturn After Taxes On Distributions and Sale of Fund Shares4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalseViking Small-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_S000026085Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseRussell 2000 Value Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldivmf1082744_RussellTwoThousandValueIndexMemberrr_PerformanceMeasureAxisexplicitMemberViking Small-Cap Value FundRussell 2000 Value IndexStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(reflects no deduction for fees, expenses or taxes)(reflects no deduction for fees, expenses or taxes)falsefalsefalsetruefalse2truetruetrue0.24500.2450falsefalsefalsetruefalse3truetruetrue0.03520.0352falsefalsefalsetruefalse4truetruetrue0.08100.0810falsefalsefalsetruefalse5falsetruefalse002001-05-032001-05-03falsefalsetruetruefalseOthernanafalsefalseRussell 2000 Value Index54Average Annual Total Returns Viking Small-Cap Value FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]181Risk/Return SummaryUnKnownUnKnownUnKnownUnKnownfalsetrue