Risk/Return Detail Data - FidelityInternationalRealEstateFund-RetailPRO - USD ($)			12 Months Ended											60 Months Ended	84 Months Ended		120 Months Ended
		Sep. 29, 2025	Sep. 29, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 29, 2025	Sep. 29, 2025	[3]	Sep. 29, 2025
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund | Fidelity International Real Estate Fund
Prospectus Line Items
Management Fees (as a percentage of Assets)		0.82%
Distribution and Service (12b-1) Fees		0.00%
Other Expenses (as a percentage of Assets):		0.06%
Expenses (as a percentage of Assets)		0.88%
Expense Example, with Redemption, 1 Year		$ 90
Expense Example, with Redemption, 3 Years		281
Expense Example, with Redemption, 5 Years		488
Expense Example, with Redemption, 10 Years		$ 1,084
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(9.48%)											(3.98%)			2.21%
Annual Return [Percent]				(9.48%)	4.02%	(26.66%)	11.87%	5.70%	27.92%	(6.14%)	26.69%	(1.56%)	1.79%
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund
Prospectus Line Items
Risk/Return [Heading]		Fund Summary Fund /Class: Fidelity® International Real Estate Fund /Fidelity® International Real Estate Fund
Objective [Heading]		Investment Objective
Objective, Primary [Text Block]		Fidelity® International Real Estate Fund seeks capital appreciation.
Expense Heading [Optional Text]		Fee Table
Expense Narrative [Text Block]		The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Shareholder Fees Caption [Optional Text]		Shareholder fees
Shareholder Fee, Other		$ 0
Operating Expenses Caption [Optional Text]		Annual Operating Expenses
Portfolio Turnover [Heading]		Portfolio Turnover
Portfolio Turnover [Text Block]		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 77 % of the average value of its portfolio.
Portfolio Turnover, Rate		77.00%
Expense Example Narrative [Text Block]		This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the 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:
Strategy [Heading]		Principal Investment Strategies
Strategy Narrative [Text Block]		Normally investing primarily in non-U.S. securities. The Adviser considers non-U.S. securities to include investments that are tied economically to a particular country or region outside the U.S. Normally investing primarily in common stocks. Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments. A real estate entity or real estate related investment is any company that is principally engaged in the real estate industry and includes commercial and residential mortgage-backed securities; debt securities of real estate entities; equity securities of entities whose primary assets are mortgage loans or commercial or residential mortgage-backed securities; REITs that either own properties or make construction loans and preferred stocks of REITs; real estate developers; companies with substantial real estate holdings; and other companies whose products and services are related to the real estate industry, such as building supply manufacturers, mortgage lenders, or mortgage servicing companies. The Adviser considers a company to be principally engaged in the real estate industry if (i) at least 50% of its assets, income, sales or profits are committed to, or derived from, the real estate industry, or (ii) a third party has given the company an industry or sector classification consistent with the real estate industry. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.   Allocating investments across different countries and regions. 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.
Strategy Portfolio Concentration [Text]		Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments.
Bar Chart and Performance Table [Heading]		Performance
Performance Narrative [Text Block]		The following information is intended to help you understand the risks of investing in the fund. 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. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for more recent performance information.
Performance Information Illustrates Variability of Returns [Text]		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.
Performance Availability Website Address [Text]		www.fidelity.com
Performance Past Does Not Indicate Future [Text]		Past performance (before and after taxes) is not an indication of future performance.
Bar Chart [Heading]		Year-by-Year Returns
Year to Date Return, Label [Optional Text]		Year-to-Date Return
Bar Chart, Year to Date Return, Date		Jun. 30, 2025
Bar Chart, Year to Date Return		17.57%
Highest Quarterly Return, Label [Optional Text]		Highest Quarter Return
Highest Quarterly Return, Date		Sep. 30, 2024
Highest Quarterly Return		13.58%
Lowest Quarterly Return, Label [Optional Text]		Lowest Quarter Return
Lowest Quarterly Return, Date		Mar. 31, 2020
Lowest Quarterly Return		(19.83%)
Performance Table Heading		Average Annual Returns
Performance Table Uses Highest Federal Rate		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.
Performance Table Not Relevant to Tax Deferred		The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
Performance Table Explanation after Tax Higher		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.
Performance Table Narrative		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. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). 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.
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund | After Taxes on Distributions | Fidelity International Real Estate Fund
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions
Average Annual Return, Percent			(10.61%)											(4.84%)			1.21%
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund | After Taxes on Distributions and Sales | Fidelity International Real Estate Fund
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions and Sale of Fund Shares
Average Annual Return, Percent			(4.92%)											(2.90%)			1.62%
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund | RT004
Prospectus Line Items
Average Annual Return, Label [Optional Text]			FTSE® EPRA℠/NAREIT® Developed ex North America Index
Average Annual Return, Percent			(7.83%)											(5.46%)			0.31%
FidelityInternationalRealEstateFund-RetailPRO | Fidelity International Real Estate Fund | MS001
Prospectus Line Items
Average Annual Return, Label [Optional Text]			MSCI EAFE Index
Average Annual Return, Percent			4.07%											4.95%			5.41%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | Fidelity Advisor International Real Estate Fund - Class A
Prospectus Line Items
Maximum Cumulative Sales Charge (as a percentage of Offering Price)		5.75%
Maximum Deferred Sales Charge (as a percentage)	[1]	0.00%
Management Fees (as a percentage of Assets)		0.86%
Distribution and Service (12b-1) Fees		0.25%
Other Expenses (as a percentage of Assets):		0.07%
Expenses (as a percentage of Assets)		1.18%
Expense Example, with Redemption, 1 Year		$ 688
Expense Example, with Redemption, 3 Years		928
Expense Example, with Redemption, 5 Years		1,187
Expense Example, with Redemption, 10 Years		1,924
Expense Example, No Redemption, 1 Year		688
Expense Example, No Redemption, 3 Years		928
Expense Example, No Redemption, 5 Years		1,187
Expense Example, No Redemption, 10 Years		$ 1,924
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(14.92%)											(5.35%)			1.34%
Annual Return [Percent]				(9.73%)	3.82%	(26.87%)	11.63%	5.34%	27.50%	(6.46%)	26.48%	(1.83%)	1.60%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | Fidelity Advisor International Real Estate Fund - Class M
Prospectus Line Items
Maximum Cumulative Sales Charge (as a percentage of Offering Price)		3.50%
Maximum Deferred Sales Charge (as a percentage)	[1]	0.00%
Management Fees (as a percentage of Assets)		0.86%
Distribution and Service (12b-1) Fees		0.50%
Other Expenses (as a percentage of Assets):		0.07%
Expenses (as a percentage of Assets)		1.43%
Expense Example, with Redemption, 1 Year		$ 490
Expense Example, with Redemption, 3 Years		787
Expense Example, with Redemption, 5 Years		1,104
Expense Example, with Redemption, 10 Years		2,003
Expense Example, No Redemption, 1 Year		490
Expense Example, No Redemption, 3 Years		787
Expense Example, No Redemption, 5 Years		1,104
Expense Example, No Redemption, 10 Years		$ 2,003
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(13.08%)											(5.17%)			1.28%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | Fidelity Advisor International Real Estate Fund - Class C
Prospectus Line Items
Maximum Cumulative Sales Charge (as a percentage of Offering Price)		0.00%
Maximum Deferred Sales Charge (as a percentage)	[2]	1.00%
Management Fees (as a percentage of Assets)		0.86%
Distribution and Service (12b-1) Fees		1.00%
Other Expenses (as a percentage of Assets):		0.07%
Expenses (as a percentage of Assets)		1.93%
Expenses Deferred Charges [Text Block]		On Class C shares redeemed less than one year after purchase.
Expense Example, with Redemption, 1 Year		$ 296
Expense Example, with Redemption, 3 Years		606
Expense Example, with Redemption, 5 Years		1,042
Expense Example, with Redemption, 10 Years		2,059
Expense Example, No Redemption, 1 Year		196
Expense Example, No Redemption, 3 Years		606
Expense Example, No Redemption, 5 Years		1,042
Expense Example, No Redemption, 10 Years		$ 2,059
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(11.29%)											(4.97%)			1.34%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | Fidelity Advisor International Real Estate Fund - Class I
Prospectus Line Items
Maximum Cumulative Sales Charge (as a percentage of Offering Price)		0.00%
Maximum Deferred Sales Charge (as a percentage)		0.00%
Management Fees (as a percentage of Assets)		0.84%
Distribution and Service (12b-1) Fees		0.00%
Other Expenses (as a percentage of Assets):		0.06%
Expenses (as a percentage of Assets)		0.90%
Expense Example, with Redemption, 1 Year		$ 92
Expense Example, with Redemption, 3 Years		287
Expense Example, with Redemption, 5 Years		498
Expense Example, with Redemption, 10 Years		1,108
Expense Example, No Redemption, 1 Year		92
Expense Example, No Redemption, 3 Years		287
Expense Example, No Redemption, 5 Years		498
Expense Example, No Redemption, 10 Years		$ 1,108
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(9.45%)											(3.92%)			2.29%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | Fidelity Advisor International Real Estate Fund - Class Z
Prospectus Line Items
Maximum Cumulative Sales Charge (as a percentage of Offering Price)		0.00%
Maximum Deferred Sales Charge (as a percentage)		0.00%
Management Fees (as a percentage of Assets)		0.72%
Distribution and Service (12b-1) Fees		0.00%
Other Expenses (as a percentage of Assets):		0.06%
Expenses (as a percentage of Assets)		0.78%
Expense Example, with Redemption, 1 Year		$ 80
Expense Example, with Redemption, 3 Years		249
Expense Example, with Redemption, 5 Years		433
Expense Example, with Redemption, 10 Years		966
Expense Example, No Redemption, 1 Year		80
Expense Example, No Redemption, 3 Years		249
Expense Example, No Redemption, 5 Years		433
Expense Example, No Redemption, 10 Years		$ 966
Annual Return, Inception Date		Oct. 02, 2018
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			(9.42%)											(3.83%)	0.11%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund
Prospectus Line Items
Risk/Return [Heading]		Fund Summary Fund /Class: Fidelity® International Real Estate Fund /Fidelity Advisor® International Real Estate Fund A, M, C, I, Z
Objective [Heading]		Investment Objective
Objective, Primary [Text Block]		Fidelity® International Real Estate Fund seeks capital appreciation.
Expense Heading [Optional Text]		Fee Table
Expense Narrative [Text Block]		The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 35 of the prospectus and in the sales charge waiver appendix to the prospectus.
Shareholder Fees Caption [Optional Text]		Shareholder fees
Operating Expenses Caption [Optional Text]		Annual Operating Expenses
Portfolio Turnover [Heading]		Portfolio Turnover
Portfolio Turnover [Text Block]		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 77 % of the average value of its portfolio.
Portfolio Turnover, Rate		77.00%
Expenses Deferred Charges [Text Block]		Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% and 0.25%, respectively.
Expense Breakpoint Discounts [Text]		You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 35 of the prospectus
Expense Breakpoint, Minimum Investment Required [Amount]		$ 50,000
Expense Example Narrative [Text Block]		This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the 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:
Strategy [Heading]		Principal Investment Strategies
Strategy Narrative [Text Block]		Normally investing primarily in non-U.S. securities. The Adviser considers non-U.S. securities to include investments that are tied economically to a particular country or region outside the U.S. Normally investing primarily in common stocks. Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments. A real estate entity or real estate related investment is any company that is principally engaged in the real estate industry and includes commercial and residential mortgage-backed securities; debt securities of real estate entities; equity securities of entities whose primary assets are mortgage loans or commercial or residential mortgage-backed securities; REITs that either own properties or make construction loans and preferred stocks of REITs; real estate developers; companies with substantial real estate holdings; and other companies whose products and services are related to the real estate industry, such as building supply manufacturers, mortgage lenders, or mortgage servicing companies. The Adviser considers a company to be principally engaged in the real estate industry if (i) at least 50% of its assets, income, sales or profits are committed to, or derived from, the real estate industry, or (ii) a third party has given the company an industry or sector classification consistent with the real estate industry. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.   Allocating investments across different countries and regions. 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.
Strategy Portfolio Concentration [Text]		Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments.
Bar Chart and Performance Table [Heading]		Performance
Performance Narrative [Text Block]		The following information is intended to help you understand the risks of investing in the fund. 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. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit institutional.fidelity.com for more recent performance information.
Performance Information Illustrates Variability of Returns [Text]		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.
Performance Availability Website Address [Text]		institutional.fidelity.com
Performance Past Does Not Indicate Future [Text]		Past performance (before and after taxes) is not an indication of future performance.
Bar Chart [Heading]		Year-by-Year Returns
Bar Chart Narrative [Text Block]		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.
Bar Chart Does Not Reflect Sales Loads [Text]		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.
Year to Date Return, Label [Optional Text]		Year-to-Date Return
Bar Chart, Year to Date Return, Date		Jun. 30, 2025
Bar Chart, Year to Date Return		17.37%
Highest Quarterly Return, Label [Optional Text]		Highest Quarter Return
Highest Quarterly Return, Date		Sep. 30, 2024
Highest Quarterly Return		13.56%
Lowest Quarterly Return, Label [Optional Text]		Lowest Quarter Return
Lowest Quarterly Return, Date		Mar. 31, 2020
Lowest Quarterly Return		(19.84%)
Performance Table Heading		Average Annual Returns
Performance Table Does Reflect Sales Loads		Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.
Performance Table Uses Highest Federal Rate		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.
Performance Table Not Relevant to Tax Deferred		The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
Performance Table One Class of after Tax Shown [Text]		After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.
Performance Table Explanation after Tax Higher		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.
Performance Table Narrative		Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. 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. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). 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.
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | After Taxes on Distributions | Fidelity Advisor International Real Estate Fund - Class A
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions
Average Annual Return, Percent			(15.92%)											(6.14%)			0.43%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | After Taxes on Distributions and Sales | Fidelity Advisor International Real Estate Fund - Class A
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions and Sale of Fund Shares
Average Annual Return, Percent			(8.17%)											(3.89%)			0.98%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | RT004
Prospectus Line Items
Average Annual Return, Label [Optional Text]			FTSE® EPRA℠/NAREIT® Developed ex North America Index
Average Annual Return, Percent			(7.83%)											(5.46%)			0.31%
FidelityInternationalRealEstateFund-AMCIZPRO | Fidelity International Real Estate Fund | MS001
Prospectus Line Items
Average Annual Return, Label [Optional Text]			MSCI EAFE Index
Average Annual Return, Percent			4.07%											4.95%			5.41%
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio | Fidelity Real Estate Investment Portfolio
Prospectus Line Items
Management Fees (as a percentage of Assets)		0.63%
Distribution and Service (12b-1) Fees		0.00%
Other Expenses (as a percentage of Assets):		0.01%
Expenses (as a percentage of Assets)		0.64%
Expense Example, with Redemption, 1 Year		$ 65
Expense Example, with Redemption, 3 Years		205
Expense Example, with Redemption, 5 Years		357
Expense Example, with Redemption, 10 Years		$ 798
Average Annual Return, Label [Optional Text]			Return Before Taxes
Average Annual Return, Percent			5.81%											3.08%			5.24%
Annual Return [Percent]				5.81%	10.87%	(24.30%)	42.35%	(7.93%)	25.20%	(3.95%)	4.27%	7.77%	5.95%
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio
Prospectus Line Items
Risk/Return [Heading]		Fund Summary Fund: Fidelity® Real Estate Investment Portfolio
Objective [Heading]		Investment Objective
Objective, Primary [Text Block]		Fidelity® Real Estate Investment Portfolio seeks above-average income and long-term capital growth, consistent with reasonable investment risk. The fund seeks to provide a yield that exceeds the composite yield of the S&P 500 ® Index.
Expense Heading [Optional Text]		Fee Table
Expense Narrative [Text Block]		The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions , which are not reflected in the tables and examples below.
Shareholder Fees Caption [Optional Text]		Shareholder fees
Shareholder Fee, Other		$ 0
Operating Expenses Caption [Optional Text]		Annual Operating Expenses
Portfolio Turnover [Heading]		Portfolio Turnover
Portfolio Turnover [Text Block]		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 35 % of the average value of its portfolio.
Portfolio Turnover, Rate		35.00%
Expense Example Narrative [Text Block]		This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the 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:
Strategy [Heading]		Principal Investment Strategies
Strategy Narrative [Text Block]		Normally investing primarily in common stocks. Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments. A real estate entity or real estate related investment is any company that is principally engaged in the real estate industry and includes commercial and residential mortgage-backed securities; debt securities of real estate entities; equity securities of entities whose primary assets are mortgage loans or commercial or residential mortgage-backed securities; REITs that either own properties or make construction loans and preferred stocks of REITs; real estate developers; companies with substantial real estate holdings; and other companies whose products and services are related to the real estate industry, such as building supply manufacturers, mortgage lenders, or mortgage servicing companies. The Adviser considers a company to be principally engaged in the real estate industry if (i) at least 50% of its assets, income, sales or profits are committed to, or derived from, the real estate industry, or (ii) a third party has given the company an industry or sector classification consistent with the real estate industry. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.   Investing in domestic and foreign issuers. 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.
Strategy Portfolio Concentration [Text]		Normally investing at least 80% of assets in securities of companies principally engaged in the real estate industry and other real estate related investments.
Bar Chart and Performance Table [Heading]		Performance
Performance Narrative [Text Block]		The following information is intended to help you understand the risks of investing in the fund. 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. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for more recent performance information.
Performance Information Illustrates Variability of Returns [Text]		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.
Performance Availability Website Address [Text]		www.fidelity.com
Performance Past Does Not Indicate Future [Text]		Past performance (before and after taxes) is not an indication of future performance.
Bar Chart [Heading]		Year-by-Year Returns
Year to Date Return, Label [Optional Text]		Year-to-Date Return
Bar Chart, Year to Date Return, Date		Jun. 30, 2025
Bar Chart, Year to Date Return		2.47%
Highest Quarterly Return, Label [Optional Text]		Highest Quarter Return
Highest Quarterly Return, Date		Sep. 30, 2024
Highest Quarterly Return		17.19%
Lowest Quarterly Return, Label [Optional Text]		Lowest Quarter Return
Lowest Quarterly Return, Date		Mar. 31, 2020
Lowest Quarterly Return		(23.29%)
Performance Table Heading		Average Annual Returns
Performance Table Uses Highest Federal Rate		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.
Performance Table Not Relevant to Tax Deferred		The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
Performance Table Explanation after Tax Higher		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.
Performance Table Narrative		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. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). 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.
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio | After Taxes on Distributions | Fidelity Real Estate Investment Portfolio
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions
Average Annual Return, Percent			4.24%											1.43%			3.59%
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio | After Taxes on Distributions and Sales | Fidelity Real Estate Investment Portfolio
Prospectus Line Items
Average Annual Return, Label [Optional Text]			Return After Taxes on Distributions and Sale of Fund Shares
Average Annual Return, Percent			4.17%											2.10%			3.74%
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio | IXWEJ
Prospectus Line Items
Average Annual Return, Label [Optional Text]			MSCI US IMI Real Estate 25/50 Linked Index
Average Annual Return, Percent			5.05%											0.97%			3.65%
FidelityRealEstateInvestmentPortfolio-PRO | Fidelity Real Estate Investment Portfolio | SP001
Prospectus Line Items
Average Annual Return, Label [Optional Text]			S&P 500® Index
Average Annual Return, Percent			25.02%											14.53%			13.10%
Document Type		485BPOS
Registrant Name		Fidelity Select Portfolios

[1] A Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% and 0.25%, respectively.

[2] B On Class C shares redeemed less than one year after purchase.

[3] A From October 2, 2018 .