2.2.0.25truefalse004601 - Document - Risk/Return Summary {Unlabeled} - (Telecommunications Portfolio) (ATBC)falsefalsetrue1falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : T B C Member {dei_LegalEntityAxis} : S000007485 Member 4/29/2011 - 4/29/2011 USD ($) $Duration_4_29_2011_To_4_29_2011_dei_DocumentInformationDocumentAxis_cik0000320351_TBCMember_dei_LegalEntityAxis_cik0000320351_S000007485Memberhttp://www.sec.gov/CIK0000320351duration2011-04-29T00:00:002011-04-29T00:00:00falsefalsecik0000320351_TBCMemberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsecik0000320351_S000007485Memberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.fidelity.com/role/documentriskreturnsummaryunlabeledtelecommunicationsportfolioatbc1falsefalsefalse00A T B C | Telecommunications PortfolioA T B C | Telecommunications Portfoliofalsefalsefalsefalsefalse1falsefalseUSDtruefalse{dei_DocumentInformationDocumentAxis} : T B C Member {dei_LegalEntityAxis} : S000007485 Member 4/29/2011 - 4/29/2011 USD ($) $Duration_4_29_2011_To_4_29_2011_dei_DocumentInformationDocumentAxis_cik0000320351_TBCMember_dei_LegalEntityAxis_cik0000320351_S000007485Memberhttp://www.sec.gov/CIK0000320351duration2011-04-29T00:00:002011-04-29T00:00:00falsefalsecik0000320351_TBCMemberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsecik0000320351_S000007485Memberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseA T B C | Telecommunications Portfolio3false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData">&nbsp;<b> </b> <h1 align="left"><a name="fid371"> </a>Fund Summary</h1> <p align="left"> </p><a name="ref1887395"> </a>Fund/<b>Class:</b><br />Telecommunications Portfolio/<b>Fidelity Advisor Telecommunications Fund A,</b> <b>T,</b> <b>B,</b> <b>C</b> <p> </p></div>falsefalsefalsefalsefalseOtherxbrli: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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Investment Objective</h3></div>falsefalsefalsefalsefalseOtherxbrli: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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p align="left">The fund seeks capital appreciation. </p></div> </div>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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Fee Table</h3></div>falsefalsefalsefalsefalseOtherxbrli: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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p align="left">The following table describes the fees and expenses that may be incurred when you buy, hold, or sell shares of the fund. </p> <p align="left"><font class="_mt">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least&nbsp;<font class="_mt">$50,000</font> in the fund or certain other Fidelity funds.</font>More information about these and other discounts is available from your investment professional and in the Fund Distribution section beginning on page &lt;Click Here&gt; of the prospectus. </p></div> </div>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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <p align="left"><b>Shareholder fees<br /><font class="_mt" size="-2">(fees paid directly from your investment)</font></b></p></div>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://www.fidelity.com/role/ScheduleShareholderFeesTelecommunicationsPortfolioAtbc column period compact * column dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember column dei_LegalEntityAxis compact cik0000320351_S000007485Member column rr_ProspectusShareClassAxis compact * row primary compact * ~&lt;/div&gt; 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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) on purchases (as a % of offering price)0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricetruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.05750.0575falsefalsefalsetruefalse2truetruetrue0.0350.035falsefalsefalsetruefalse3truetruetrue00falsefalsefalsetruefalse4truetruetrue00falsefalsefalsetruefalseOthernanafalsefalseMaximum sales charge (load) on purchases (as a % of offering price)2falseRowprimaryElement*6false0rr_MaximumDeferredSalesChargeOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00[2]falsefalsefalsetruefalse2truetruetrue00[2]falsefalsefalsetruefalse3truetruetrue0.050.05[1]falsefalsefalsetruefalse4truetruetrue0.010.01[3]falsefalsefalsetruefalseOtherrr: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 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)0rr_MaximumDeferredSalesChargeOverOfferingPricetruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00[1]falsefalsefalsetruefalse2truetruetrue00[1]falsefalsefalsetruefalse3truetruetrue0.050.05[2]falsefalsefalsetruefalse4truetruetrue0.010.01[3]falsefalsefalsetruefalseOthernanafalsefalseMaximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)3falseRowprimaryElement*7false0rr_RedemptionFeeOverRedemptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truetruetrue0.00750.0075falsefalsefalsetruefalse2truetruetrue0.00750.0075falsefalsefalsetruefalse3truetruetrue0.00750.0075falsefalsefalsetruefalse4truetruetrue0.00750.0075falsefalsefalsetruefalseOtherrr: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 on shares held less than 30 days (as a % of amount redeemed)0rr_RedemptionFeeOverRedemptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00750.0075falsefalsefalsetruefalse2truetruetrue0.00750.0075falsefalsefalsetruefalse3truetruetrue0.00750.0075falsefalsefalsetruefalse4truetruetrue0.00750.0075falsefalsefalsetruefalseOthernanafalsefalseRedemption fee on shares held less than 30 days (as a % of amount redeemed)1 Class A and Class T purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class T purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.2 Declines over 6 years from 5.00% to 0%.3 On Class C shares redeemed less than one year after purchase.43Shareholder Fees - A T B C Telecommunications PortfolioUnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*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.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <p align="left"><b>Annual class operating expenses<br /><font class="_mt" size="-2">(expenses that you pay each year as a % of the value of your investment)</font></b> </p></div>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://www.fidelity.com/role/ScheduleAnnualFundOperatingExpensesTelecommunicationsPortfolioAtbc1 column period compact * column dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember column dei_LegalEntityAxis compact cik0000320351_S000007485Member column rr_ProspectusShareClassAxis compact * row primary compact * 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Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Trr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040634Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass TUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Brr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040632Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass BUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$4falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Crr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040633Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass CUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*5false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00560.0056falsefalsefalsetruefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3truetruetrue0.00560.0056falsefalsefalsetruefalse4truetruetrue0.00560.0056falsefalsefalsetruefalseOtherrr: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 fee0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00560.0056falsefalsefalsetruefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3truetruetrue0.00560.0056falsefalsefalsetruefalse4truetruetrue0.00560.0056falsefalsefalsetruefalseOthernanafalsefalseManagement fee2falseRowprimaryElement*6false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00250.0025falsefalsefalsetruefalse2truetruetrue0.00500.0050falsefalsefalsetruefalse3truetruetrue0.01000.0100falsefalsefalsetruefalse4truetruetrue0.01000.0100falsefalsefalsetruefalseOtherrr: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/or Service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00250.0025falsefalsefalsetruefalse2truetruetrue0.00500.0050falsefalsefalsetruefalse3truetruetrue0.01000.0100falsefalsefalsetruefalse4truetruetrue0.01000.0100falsefalsefalsetruefalseOthernanafalsefalseDistribution and/or Service (12b-1) fees3falseRowprimaryElement*7false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00390.0039falsefalsefalsetruefalse2truetruetrue0.00420.0042falsefalsefalsetruefalse3truetruetrue0.00390.0039falsefalsefalsetruefalse4truetruetrue0.00380.0038falsefalsefalsetruefalseOtherrr: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_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00390.0039falsefalsefalsetruefalse2truetruetrue0.00420.0042falsefalsefalsetruefalse3truetruetrue0.00390.0039falsefalsefalsetruefalse4truetruetrue0.00380.0038falsefalsefalsetruefalseOthernanafalsefalseOther expenses4falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truetruetrue0.01200.0120falsefalsefalsetruefalse2truetruetrue0.01480.0148falsefalsefalsetruefalse3truetruetrue0.01950.0195falsefalsefalsetruefalse4truetruetrue0.01940.0194falsefalsefalsetruefalseOtherrr: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 truefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.01200.0120falsefalsefalsetruefalse2truetruetrue0.01480.0148falsefalsefalsetruefalse3truetruetrue0.01950.0195falsefalsefalsetruefalse4truetruetrue0.01940.0194falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses44Annual Fund Operating Expenses - A T B C Telecommunications PortfolioUnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*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_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <div> <p align="left">This <b>example</b> helps compare the cost of investing in the fund with the cost of investing in other mutual funds. </p></div> <div> <p align="left">Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:</p></div></div> </div>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]13false0rr_ExpenseExampleByYearCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <p align="left"><font size="1" class="_mt">Sell All Shares</font></p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThe 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 falsefalseExpense Example by, Year, Caption [Text]14false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleExpenseExampleTransposedTelecommunicationsPortfolioAtbc row period compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * column primary compact * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleExpenseExampleTransposedTelecommunicationsPortfolioAtbc row period compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * column primary compact * ~&lt;/div&gt; </div>truehttp://www.fidelity.com/role/ScheduleExpenseExampleTransposedTelecommunicationsPortfolioAtbcfalsefalse004604 - Schedule - Expense Example {Transposed} - {Telecommunications Portfolio} {ATBC}truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass AfalseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Trr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040634Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass TfalseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Brr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040632Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass BfalseUSDfalsefalse$4falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Crr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040633Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass CfalseUSDfalsefalse$1falseRowprimaryElement*RowunitUnit*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue690690falsefalsefalsetruefalse2truefalsetrue495495falsefalsefalsetruefalse3truefalsetrue698698falsefalsefalsetruefalse4truefalsetrue297297falsefalsefalsetruefalseMonetaryrr: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 yearUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear01truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue690690falsefalsefalsetruefalse2truefalsetrue495495falsefalsefalsetruefalse3truefalsetrue698698falsefalsefalsetruefalse4truefalsetrue297297falsefalsefalsetruefalseOthernanafalsefalse1 year2falseRowprimaryElement*RowunitUnit*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue934934falsefalsefalsetruefalse2truefalsetrue802802falsefalsefalsetruefalse3truefalsetrue912912falsefalsefalsetruefalse4truefalsetrue609609falsefalsefalsetruefalseMonetaryrr: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 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear03truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue934934falsefalsefalsetruefalse2truefalsetrue802802falsefalsefalsetruefalse3truefalsetrue912912falsefalsefalsetruefalse4truefalsetrue609609falsefalsefalsetruefalseOthernanafalsefalse3 years3falseRowprimaryElement*RowunitUnit*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue11971197falsefalsefalsetruefalse2truefalsetrue11301130falsefalsefalsetruefalse3truefalsetrue12521252falsefalsefalsetruefalse4truefalsetrue10471047falsefalsefalsetruefalseMonetaryrr: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 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear05truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue11971197falsefalsefalsetruefalse2truefalsetrue11301130falsefalsefalsetruefalse3truefalsetrue12521252falsefalsefalsetruefalse4truefalsetrue10471047falsefalsefalsetruefalseOthernanafalsefalse5 years4falseRowprimaryElement*RowunitUnit*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue19461946falsefalsefalsetruefalse2truefalsetrue20572057falsefalsefalsetruefalse3truefalsetrue19891989falsefalsefalsetruefalse4truefalsetrue22642264falsefalsefalsetruefalseMonetaryrr: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 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleYear10truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue19461946falsefalsefalsetruefalse2truefalsetrue20572057falsefalsefalsetruefalse3truefalsetrue19891989falsefalsefalsetruefalse4truefalsetrue22642264falsefalsefalsetruefalseOthernanafalsefalse10 years44Expense Example - A T B C Telecommunications Portfolio (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*RowprimaryElement*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_ExpenseExampleNoRedemptionByYearCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <p style="margin-top: 0px; margin-bottom: 0px;" align="left"><font size="1" class="_mt">Hold Shares</font></p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringYou would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph 1 -Subsection example falsefalseExpense Example, No Redemption, By Year, Caption [Text]16false0rr_ExpenseExampleNoRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleExpenseExampleNoRedemptionTransposedTelecommunicationsPortfolioAtbc row period compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * column primary compact * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleExpenseExampleNoRedemptionTransposedTelecommunicationsPortfolioAtbc row period compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * column primary compact * ~&lt;/div&gt; </div>truehttp://www.fidelity.com/role/ScheduleExpenseExampleNoRedemptionTransposedTelecommunicationsPortfolioAtbcfalsefalse004605 - Schedule - Expense Example, No Redemption {Transposed} - {Telecommunications Portfolio} {ATBC}truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass AfalseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Trr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040634Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass TfalseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Brr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040632Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass BfalseUSDfalsefalse$4falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*duration2011-04-29T00:00:002011-04-29T00:00:00falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Crr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040633Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass CfalseUSDfalsefalse$1falseRowprimaryElement*RowunitUnit*5false0rr_ExpenseExampleNoRedemptionYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue690690falsefalsefalsetruefalse2truefalsetrue495495falsefalsefalsetruefalse3truefalsetrue198198falsefalsefalsetruefalse4truefalsetrue197197falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryYou would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph 1 -Subsection example falsefalse1 yearUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleNoRedemptionYear01truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue690690falsefalsefalsetruefalse2truefalsetrue495495falsefalsefalsetruefalse3truefalsetrue198198falsefalsefalsetruefalse4truefalsetrue197197falsefalsefalsetruefalseOthernanafalsefalse1 year2falseRowprimaryElement*RowunitUnit*6false0rr_ExpenseExampleNoRedemptionYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue934934falsefalsefalsetruefalse2truefalsetrue802802falsefalsefalsetruefalse3truefalsetrue612612falsefalsefalsetruefalse4truefalsetrue609609falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryYou would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph 1 -Subsection example falsefalse3 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleNoRedemptionYear03truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue934934falsefalsefalsetruefalse2truefalsetrue802802falsefalsefalsetruefalse3truefalsetrue612612falsefalsefalsetruefalse4truefalsetrue609609falsefalsefalsetruefalseOthernanafalsefalse3 years3falseRowprimaryElement*RowunitUnit*7false0rr_ExpenseExampleNoRedemptionYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue11971197falsefalsefalsetruefalse2truefalsetrue11301130falsefalsefalsetruefalse3truefalsetrue10521052falsefalsefalsetruefalse4truefalsetrue10471047falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryYou would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subparagraph f -Subsection instructions falsefalse5 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleNoRedemptionYear05truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue11971197falsefalsefalsetruefalse2truefalsetrue11301130falsefalsefalsetruefalse3truefalsetrue10521052falsefalsefalsetruefalse4truefalsetrue10471047falsefalsefalsetruefalseOthernanafalsefalse5 years4falseRowprimaryElement*RowunitUnit*8false0rr_ExpenseExampleNoRedemptionYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsetrue19461946falsefalsefalsetruefalse2truefalsetrue20572057falsefalsefalsetruefalse3truefalsetrue19891989falsefalsefalsetruefalse4truefalsetrue22642264falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryYou would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subparagraph f -Subsection instructions falsefalse10 yearsUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700rr_ExpenseExampleNoRedemptionYear10truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue19461946falsefalsefalsetruefalse2truefalsetrue20572057falsefalsefalsetruefalse3truefalsetrue19891989falsefalsefalsetruefalse4truefalsetrue22642264falsefalsefalsetruefalseOthernanafalsefalse10 years44Expense Example, No Redemption - A T B C Telecommunications Portfolio (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberColumndei_LegalEntityAxisAxiscik0000320351_S000007485MemberColumnrr_ProspectusShareClassAxisAxis*RowprimaryElement*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExampleNoRedemption.No authoritative reference available.falsefalseExpense Example, No Redemption [Table]17false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Portfolio Turnover</h3></div>falsefalsefalsefalsefalseOtherxbrli: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]18false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p align="left">The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was&nbsp;<font class="_mt">72%</font> of the average value of its portfolio.</p></div> </div>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]19false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Principal Investment Strategies</h3></div>falsefalsefalsefalsefalseOtherxbrli: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]20false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <ul> <li>Normally investing primarily in common stocks. </li> <li>Normally investing at least 80% of assets in securities of companies principally engaged in the development, manufacture, or sale of communications services or communications equipment. </li> <li>Investing in domestic and foreign issuers. </li> <li>Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions to select investments. </li></ul></div> </div>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]21false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Principal Investment Risks</h3></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]22false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <ul> <li><i>Stock Market Volatility.</i> 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. </li> <li><i>Foreign Exposure.</i> Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. </li></ul> <ul> <li><i>Telecom Services Industry Concentration.</i> The telecom services industry is subject to government regulation of rates of return and services that may be offered and can be significantly affected by intense competition. </li> <li><i>Issuer-Specific Changes.</i> The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers. </li></ul> <div> <p align="left">In addition,&nbsp;<font class="_mt">the fund is considered non-diversified and can invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund.</font> As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund. </p></div> <p align="left"><font class="_mt">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.</font><font class="_mt">You could lose money by investing in the fund.</font></p></div> </div>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]23false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Performance</h3></div>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 and Performance Table [Heading]24false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p align="left">The following information is intended to help you understand the risks of investing in the fund.&nbsp;<font class="_mt">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font> The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the Additional Information about the Indexes section of the prospectus. <font class="_mt">Past performance (before and after taxes) is not an indication of future performance.</font></p> <p align="left">Visit&nbsp;<font class="_mt">www.advisor.fidelity.com</font> for updated return information. </p> <p align="left">&nbsp;</p></div> </div>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]25false0rr_BarChartDoesNotReflectSalesLoadsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <p align="left"><font class="_mt">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown</font>. </p></div>falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInclude the bar chart and table required by Item 4 (b)(2)(ii) and (iii) of this section. Provide a brief explanation of how the information illustrates the variability of the Fund's returns (e.g., by stating that the information provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance). Provide a statement to the effect that the Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Provide annual total returns beginning with the earliest calendar year. Calculate annual returns using the Instructions to Item 8(a), except that the calculations should be based on calendar years. If a Fund's shares are sold subject to a sales load or account fees, state that sales loads or account fees are not reflected in the bar chart and that, if these amounts were reflected, returns would be less than those shown.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph i -Subsection b falsefalseBar Chart Does Not Reflect Sales Loads [Text]26false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <div> <h3 align="left">Year-by-Year Returns</h3> <p style="margin-top: 0px; margin-bottom: 0px;" align="left"><font size="1" class="_mt">Calendar Years</font></p></div></div>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]27false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleAnnualTotalReturnsTelecommunicationsPortfolioAtbcBarChart column period compact * column primary compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * ~&lt;/div&gt; </div>falsefalseBarChart46.jpg<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleAnnualTotalReturnsTelecommunicationsPortfolioAtbcBarChart column period compact * column primary compact * row dei_DocumentInformationDocumentAxis compact cik0000320351_TBCMember row dei_LegalEntityAxis compact cik0000320351_S000007485Member row rr_ProspectusShareClassAxis compact * ~&lt;/div&gt; </div>falsehttp://www.fidelity.com/role/ScheduleAnnualTotalReturnsTelecommunicationsPortfolioAtbcBarChartfalsefalse004606 - Schedule - Annual Total Returns - {Telecommunications Portfolio} {ATBC} {Bar Chart}truefalsefalse1falseColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*11false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07920.0792falsefalsefalsetruefalseOtherxbrli: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 falsefalseAnnual Return 2007duration2011-04-29T00:00:002011-04-29T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$2falseColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*12false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.4780-0.4780falsefalsefalsetruefalseOtherxbrli: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 falsefalseAnnual Return 2008duration2011-04-29T00:00:002011-04-29T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*13false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.51190.5119falsefalsefalsetruefalseOtherxbrli: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 falsefalseAnnual Return 2009duration2011-04-29T00:00:002011-04-29T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$4falseColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*14false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.18010.1801falsefalsefalsetruefalseOtherxbrli: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 falsefalseAnnual Return 2010duration2011-04-29T00:00:002011-04-29T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMemberA T B CTelecommunications PortfolioClass A0truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07920.0792falsefalsefalsetruefalse2truetruefalse-0.4780-0.4780falsefalsefalsetruefalse3truetruefalse0.51190.5119falsefalsefalsetruefalse4truetruefalse0.18010.1801falsefalsefalsetruefalseOthernanafalsefalseA T B C Telecommunications Portfolio Class A41Annual Total Returns - UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*ColumnprimaryElement*ColumnunitUnit*Rowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]28false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p style="margin-top: 0px; margin-bottom: 0px;" align="left">&nbsp;</p> <p align="left"> </p> <table border="1" width="95%"> <tr><td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">During the periods shown in the chart</font></i><font class="_mt" size="-1"> <i>for Class A:</i></font> </p></td> <td valign="bottom" align="center"> <p align="center"><i><font class="_mt" size="-2">Returns</font></i> </p></td> <td valign="bottom" align="center"> <p align="center"><i><font class="_mt" size="-2">Quarter ended</font></i></p></td></tr> <tr><td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">Highest Quarter Return</font></i> </p></td> <td valign="bottom" align="left"> <p align="right"><i><font class="_mt" size="-1">18.58%</font></i> </p></td> <td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">June 30, 2009</font></i></p></td></tr> <tr><td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">Lowest Quarter Return</font></i> </p></td> <td valign="bottom" align="left"> <p align="right"><i><font class="_mt" size="-1">-22.06%</font></i> </p></td> <td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">December 31, 2008</font></i></p></td></tr> <tr><td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">Year-to-Date Return</font></i> </p></td> <td valign="bottom" align="left"> <p align="right"><i><font class="_mt" size="-1">3.80%</font></i> </p></td> <td valign="bottom" align="left"> <p align="left"><i><font class="_mt" size="-1">March 31, 2011</font></i></p></td></tr></table></div> </div>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]29false0rr_PerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div class="MetaData"> <h3 align="left">Average Annual Returns </h3></div>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 3 -Exhibit c -Subsection b falsefalsePerformance Table Heading30false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> <div class="MetaData"> <p style="margin-top: 0px; margin-bottom: 0px;" align="left"><font class="_mt">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>&nbsp;<font class="_mt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>&nbsp;<font class="_mt">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.</font> <font class="_mt">Actual after-tax returns may differ depending on your individual circumstances.&nbsp;<font class="_mt">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement.</font>&nbsp;</font><font class="_mt">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font> </p> <p style="margin-top: 0px; margin-bottom: 0px;" align="left">&nbsp;</p> <p style="margin-top: 0px; margin-bottom: 0px;" align="left"><font class="_mt" size="-2">For the periods ended<br />December 31, 2010</font> </p></div> </div>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 Narrative31false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;" &gt;~ http://www.fidelity.com/role/ScheduleAverageAnnualTotalReturnsTransposedTelecommunicationsPortfolioAtbc row period compact * row primary compact * column dei_DocumentInformationDocumentAxis compact 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.11220.1122falsefalsefalsetruefalse2truetruetrue0.10930.1093falsefalsefalsetruefalse3truetruetrue0.07650.0765falsefalsefalsetruefalse4truetruetrue0.13550.1355falsefalsefalsetruefalse5truetruetrue0.12100.1210falsefalsefalsetruefalse6truetruetrue0.16100.1610falsefalsefalsetruefalse7truetruetrue0.15060.1506falsefalsefalsetruefalse8truetruetrue0.19440.1944falsefalsefalsetruefalseOtherxbrli: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 falsefalsePast 1 yearduration2011-04-29T00:00:002011-04-29T00:00:00falseUSDfalsefalse$2falseColumnperiodPeriod*ColumnprimaryElement*8false0rr_AverageAnnualReturnSinceInceptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truetruetrue-0.0090-0.0090[1]falsefalsefalsetruefalse2truetruetrue-0.0110-0.0110[1]falsefalsefalsetruefalse3truetruetrue-0.0080-0.0080[1]falsefalsefalsetruefalse4truetruetrue-0.0061-0.0061[1]falsefalsefalsetruefalse5truetruetrue-0.0069-0.0069[1]falsefalsefalsetruefalse6truetruetrue-0.0019-0.0019[1]falsefalsefalsetruefalse7truetruetrue-0.0068-0.0068[1]falsefalsefalsetruefalse8truetruetrue0.00080.0008[1]falsefalsefalsetruefalseOtherxbrli: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 falsefalseLife of classduration2011-04-29T00:00:002011-04-29T00:00:00falseUSDfalsefalse$1falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMembertruefalseBefore Taxesrr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberA T B CTelecommunications PortfolioClass ABefore TaxesUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.11220.1122falsefalsefalsetruefalse2truetruetrue-0.0090-0.0090[1]falsefalsefalsetruefalseOthernanafalsefalseClass A2falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMemberfalsefalseReturn After Taxes on Distributionsrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldirr_AfterTaxesOnDistributionsMemberrr_PerformanceMeasureAxisexplicitMemberA T B CTelecommunications PortfolioClass AReturn After Taxes on DistributionsStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.10930.1093falsefalsefalsetruefalse2truetruetrue-0.0110-0.0110[1]falsefalsefalsetruefalseOthernanafalsefalseClass A Return After Taxes on Distributions3falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040631Memberrr_ProspectusShareClassAxisexplicitMemberfalsefalseReturn After Taxes on Distributions and Sale of Fund 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Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Trr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_C000040634Memberrr_ProspectusShareClassAxisexplicitMembertruefalseBefore Taxesrr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberA T B CTelecommunications PortfolioClass TBefore TaxesUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.13550.1355falsefalsefalsetruefalse2truetruetrue-0.0061-0.0061[1]falsefalsefalsetruefalseOthernanafalsefalseClass T5falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalseA T B 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taxes)rr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_SP500Memberrr_PerformanceMeasureAxisexplicitMemberA T B CTelecommunications PortfolioShare ClassesS&P 500 Index (reflects no deduction for fees, expenses, or taxes)Standard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.15060.1506falsefalsefalsetruefalse2truetruetrue-0.0068-0.0068[1]falsefalsefalsetruefalseOthernanafalsefalseS&P 500 Index (reflects no deduction for fees, expenses, or taxes)8falseRowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalseA T B Cdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_TBCMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseTelecommunications Portfoliodei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_S000007485Memberdei_LegalEntityAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberfalsefalseMSCI U.S. IM Telecommunications Services 25/50 Index (reflects no deduction for fees, expenses, or taxes)rr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldicik0000320351_MsciUSImTelecommunicationsServices2550IndexMemberrr_PerformanceMeasureAxisexplicitMemberA T B CTelecommunications PortfolioShare ClassesMSCI U.S. IM Telecommunications Services 25/50 Index (reflects no deduction for fees, expenses, or taxes)Standard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.19440.1944falsefalsefalsetruefalse2truetruetrue0.00080.0008[1]falsefalsefalsetruefalseOthernanafalsefalseMSCI U.S. IM Telecommunications Services 25/50 Index (reflects no deduction for fees, expenses, or taxes)1 From December 12, 2006.28Average Annual Total Returns - A T B C Telecommunications PortfolioUnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*ColumnprimaryElement*Rowdei_DocumentInformationDocumentAxisAxiscik0000320351_TBCMemberRowdei_LegalEntityAxisAxiscik0000320351_S000007485MemberRowrr_ProspectusShareClassAxisAxis*Rowrr_PerformanceMeasureAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]130Risk/Return Summary - (Telecommunications Portfolio) (ATBC) (A T B C, Telecommunications Portfolio)UnKnownUnKnownUnKnownUnKnownfalsetrue