v3.26.3
Shareholder Report, Holdings (Details)
Jul. 31, 2026
Fidelity Advisor Semiconductors Fund - Class Z | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.40%
Fidelity Advisor Semiconductors Fund - Class Z | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
Fidelity Advisor Semiconductors Fund - Class Z | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Semiconductors Fund - Class Z | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Fidelity Advisor Semiconductors Fund - Class Z | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class Z | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class Z | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Semiconductors Fund - Class Z | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class Z | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class Z | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
Fidelity Advisor Semiconductors Fund - Class Z | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 93.80%
Fidelity Advisor Semiconductors Fund - Class Z | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Semiconductors Fund - Class Z | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Semiconductors Fund - Class Z | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Semiconductors Fund - Class Z | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class Z | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class Z | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class Z | United States  
Holdings [Line Items]  
Percent of Net Asset Value 85.10%
Fidelity Advisor Semiconductors Fund - Class Z | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 9.10%
Fidelity Advisor Semiconductors Fund - Class Z | Japan  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Advisor Semiconductors Fund - Class Z | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Semiconductors Fund - Class Z | Taiwan  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Semiconductors Fund - Class Z | Korea, Republic of  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class Z | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class Z | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.50%
Fidelity Advisor Semiconductors Fund - Class Z | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Semiconductors Fund - Class Z | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class Z | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Semiconductors Fund - Class M | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.40%
Fidelity Advisor Semiconductors Fund - Class M | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
Fidelity Advisor Semiconductors Fund - Class M | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Semiconductors Fund - Class M | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Fidelity Advisor Semiconductors Fund - Class M | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class M | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class M | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Semiconductors Fund - Class M | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class M | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class M | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
Fidelity Advisor Semiconductors Fund - Class M | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 93.80%
Fidelity Advisor Semiconductors Fund - Class M | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Semiconductors Fund - Class M | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Semiconductors Fund - Class M | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Semiconductors Fund - Class M | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class M | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class M | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class M | United States  
Holdings [Line Items]  
Percent of Net Asset Value 85.10%
Fidelity Advisor Semiconductors Fund - Class M | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 9.10%
Fidelity Advisor Semiconductors Fund - Class M | Japan  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Advisor Semiconductors Fund - Class M | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Semiconductors Fund - Class M | Taiwan  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Semiconductors Fund - Class M | Korea, Republic of  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class M | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class M | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.50%
Fidelity Advisor Semiconductors Fund - Class M | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Semiconductors Fund - Class M | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class M | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Semiconductors Fund - Class I | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.40%
Fidelity Advisor Semiconductors Fund - Class I | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
Fidelity Advisor Semiconductors Fund - Class I | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Semiconductors Fund - Class I | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Fidelity Advisor Semiconductors Fund - Class I | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class I | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class I | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Semiconductors Fund - Class I | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class I | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class I | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
Fidelity Advisor Semiconductors Fund - Class I | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 93.80%
Fidelity Advisor Semiconductors Fund - Class I | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Semiconductors Fund - Class I | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Semiconductors Fund - Class I | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Semiconductors Fund - Class I | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class I | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class I | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class I | United States  
Holdings [Line Items]  
Percent of Net Asset Value 85.10%
Fidelity Advisor Semiconductors Fund - Class I | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 9.10%
Fidelity Advisor Semiconductors Fund - Class I | Japan  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Advisor Semiconductors Fund - Class I | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Semiconductors Fund - Class I | Taiwan  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Semiconductors Fund - Class I | Korea, Republic of  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class I | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class I | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.50%
Fidelity Advisor Semiconductors Fund - Class I | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Semiconductors Fund - Class I | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class I | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Semiconductors Fund - Class C | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.40%
Fidelity Advisor Semiconductors Fund - Class C | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
Fidelity Advisor Semiconductors Fund - Class C | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Semiconductors Fund - Class C | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Fidelity Advisor Semiconductors Fund - Class C | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class C | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class C | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Semiconductors Fund - Class C | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class C | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class C | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
Fidelity Advisor Semiconductors Fund - Class C | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 93.80%
Fidelity Advisor Semiconductors Fund - Class C | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Semiconductors Fund - Class C | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Semiconductors Fund - Class C | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Semiconductors Fund - Class C | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class C | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class C | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class C | United States  
Holdings [Line Items]  
Percent of Net Asset Value 85.10%
Fidelity Advisor Semiconductors Fund - Class C | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 9.10%
Fidelity Advisor Semiconductors Fund - Class C | Japan  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Advisor Semiconductors Fund - Class C | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Semiconductors Fund - Class C | Taiwan  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Semiconductors Fund - Class C | Korea, Republic of  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class C | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class C | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.50%
Fidelity Advisor Semiconductors Fund - Class C | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Semiconductors Fund - Class C | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class C | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Semiconductors Fund - Class A | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.40%
Fidelity Advisor Semiconductors Fund - Class A | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 15.40%
Fidelity Advisor Semiconductors Fund - Class A | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Semiconductors Fund - Class A | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
Fidelity Advisor Semiconductors Fund - Class A | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class A | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.80%
Fidelity Advisor Semiconductors Fund - Class A | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Semiconductors Fund - Class A | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class A | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.10%
Fidelity Advisor Semiconductors Fund - Class A | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.70%
Fidelity Advisor Semiconductors Fund - Class A | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 93.80%
Fidelity Advisor Semiconductors Fund - Class A | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Semiconductors Fund - Class A | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Semiconductors Fund - Class A | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Semiconductors Fund - Class A | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class A | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class A | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class A | United States  
Holdings [Line Items]  
Percent of Net Asset Value 85.10%
Fidelity Advisor Semiconductors Fund - Class A | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 9.10%
Fidelity Advisor Semiconductors Fund - Class A | Japan  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Advisor Semiconductors Fund - Class A | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Semiconductors Fund - Class A | Taiwan  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Semiconductors Fund - Class A | Korea, Republic of  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Semiconductors Fund - Class A | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class A | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.50%
Fidelity Advisor Semiconductors Fund - Class A | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Semiconductors Fund - Class A | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class A | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Semiconductors Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Industrials Fund - Class Z | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Fidelity Advisor Industrials Fund - Class Z | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Advisor Industrials Fund - Class Z | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Industrials Fund - Class Z | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Fidelity Advisor Industrials Fund - Class Z | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Industrials Fund - Class Z | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Fidelity Advisor Industrials Fund - Class Z | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class Z | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class Z | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class Z | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class Z | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Fidelity Advisor Industrials Fund - Class Z | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Fidelity Advisor Industrials Fund - Class Z | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Advisor Industrials Fund - Class Z | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Industrials Fund - Class Z | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity Advisor Industrials Fund - Class Z | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Industrials Fund - Class Z | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Industrials Fund - Class Z | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Industrials Fund - Class Z | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Advisor Industrials Fund - Class Z | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Industrials Fund - Class Z | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Fidelity Advisor Industrials Fund - Class Z | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Fidelity Advisor Industrials Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Industrials Fund - Class M | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Fidelity Advisor Industrials Fund - Class M | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Advisor Industrials Fund - Class M | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Industrials Fund - Class M | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Fidelity Advisor Industrials Fund - Class M | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Industrials Fund - Class M | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Fidelity Advisor Industrials Fund - Class M | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class M | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class M | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class M | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class M | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Fidelity Advisor Industrials Fund - Class M | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Fidelity Advisor Industrials Fund - Class M | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Advisor Industrials Fund - Class M | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Industrials Fund - Class M | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity Advisor Industrials Fund - Class M | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Industrials Fund - Class M | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Industrials Fund - Class M | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Industrials Fund - Class M | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Advisor Industrials Fund - Class M | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Industrials Fund - Class M | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Fidelity Advisor Industrials Fund - Class M | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Fidelity Advisor Industrials Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Industrials Fund - Class I | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Fidelity Advisor Industrials Fund - Class I | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Advisor Industrials Fund - Class I | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Industrials Fund - Class I | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Fidelity Advisor Industrials Fund - Class I | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Industrials Fund - Class I | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Fidelity Advisor Industrials Fund - Class I | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class I | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class I | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class I | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class I | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Fidelity Advisor Industrials Fund - Class I | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Fidelity Advisor Industrials Fund - Class I | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Advisor Industrials Fund - Class I | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Industrials Fund - Class I | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity Advisor Industrials Fund - Class I | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Industrials Fund - Class I | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Industrials Fund - Class I | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Industrials Fund - Class I | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Advisor Industrials Fund - Class I | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Industrials Fund - Class I | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Fidelity Advisor Industrials Fund - Class I | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Fidelity Advisor Industrials Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Industrials Fund - Class C | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Fidelity Advisor Industrials Fund - Class C | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Advisor Industrials Fund - Class C | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Industrials Fund - Class C | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Fidelity Advisor Industrials Fund - Class C | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Industrials Fund - Class C | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Fidelity Advisor Industrials Fund - Class C | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class C | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class C | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class C | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class C | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Fidelity Advisor Industrials Fund - Class C | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Fidelity Advisor Industrials Fund - Class C | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Advisor Industrials Fund - Class C | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Industrials Fund - Class C | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity Advisor Industrials Fund - Class C | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Industrials Fund - Class C | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Industrials Fund - Class C | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Industrials Fund - Class C | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Advisor Industrials Fund - Class C | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Industrials Fund - Class C | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Fidelity Advisor Industrials Fund - Class C | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Fidelity Advisor Industrials Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Industrials Fund - Class A | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Fidelity Advisor Industrials Fund - Class A | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Advisor Industrials Fund - Class A | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Industrials Fund - Class A | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Fidelity Advisor Industrials Fund - Class A | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Industrials Fund - Class A | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Fidelity Advisor Industrials Fund - Class A | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class A | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Industrials Fund - Class A | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class A | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Industrials Fund - Class A | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Fidelity Advisor Industrials Fund - Class A | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Fidelity Advisor Industrials Fund - Class A | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Advisor Industrials Fund - Class A | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Industrials Fund - Class A | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity Advisor Industrials Fund - Class A | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Industrials Fund - Class A | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Industrials Fund - Class A | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Industrials Fund - Class A | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Advisor Industrials Fund - Class A | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Industrials Fund - Class A | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Fidelity Advisor Industrials Fund - Class A | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Fidelity Advisor Industrials Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Financials Fund - Class Z | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Financials Fund - Class Z | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.00%
Fidelity Advisor Financials Fund - Class Z | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
Fidelity Advisor Financials Fund - Class Z | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
Fidelity Advisor Financials Fund - Class Z | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Advisor Financials Fund - Class Z | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Financials Fund - Class Z | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Financials Fund - Class Z | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
Fidelity Advisor Financials Fund - Class Z | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Financials Fund - Class Z | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Fidelity Advisor Financials Fund - Class Z | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.00%
Fidelity Advisor Financials Fund - Class Z | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 28.40%
Fidelity Advisor Financials Fund - Class Z | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 17.20%
Fidelity Advisor Financials Fund - Class Z | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.60%
Fidelity Advisor Financials Fund - Class Z | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Financials Fund - Class Z | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Financials Fund - Class Z | United States  
Holdings [Line Items]  
Percent of Net Asset Value 95.10%
Fidelity Advisor Financials Fund - Class Z | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Advisor Financials Fund - Class Z | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Financials Fund - Class Z | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class Z | GrandCaymanUKOverseasTerMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class Z | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Financials Fund - Class Z | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Financials Fund - Class Z | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.70%
Fidelity Advisor Financials Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Financials Fund - Class M | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Financials Fund - Class M | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.00%
Fidelity Advisor Financials Fund - Class M | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
Fidelity Advisor Financials Fund - Class M | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
Fidelity Advisor Financials Fund - Class M | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Advisor Financials Fund - Class M | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Financials Fund - Class M | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Financials Fund - Class M | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
Fidelity Advisor Financials Fund - Class M | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Financials Fund - Class M | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Fidelity Advisor Financials Fund - Class M | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.00%
Fidelity Advisor Financials Fund - Class M | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 28.40%
Fidelity Advisor Financials Fund - Class M | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 17.20%
Fidelity Advisor Financials Fund - Class M | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.60%
Fidelity Advisor Financials Fund - Class M | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Financials Fund - Class M | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Financials Fund - Class M | United States  
Holdings [Line Items]  
Percent of Net Asset Value 95.10%
Fidelity Advisor Financials Fund - Class M | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Advisor Financials Fund - Class M | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Financials Fund - Class M | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class M | GrandCaymanUKOverseasTerMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class M | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Financials Fund - Class M | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Financials Fund - Class M | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.70%
Fidelity Advisor Financials Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Financials Fund - Class I | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Financials Fund - Class I | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.00%
Fidelity Advisor Financials Fund - Class I | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
Fidelity Advisor Financials Fund - Class I | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
Fidelity Advisor Financials Fund - Class I | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Advisor Financials Fund - Class I | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Financials Fund - Class I | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Financials Fund - Class I | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
Fidelity Advisor Financials Fund - Class I | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Financials Fund - Class I | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Fidelity Advisor Financials Fund - Class I | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.00%
Fidelity Advisor Financials Fund - Class I | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 28.40%
Fidelity Advisor Financials Fund - Class I | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 17.20%
Fidelity Advisor Financials Fund - Class I | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.60%
Fidelity Advisor Financials Fund - Class I | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Financials Fund - Class I | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Financials Fund - Class I | United States  
Holdings [Line Items]  
Percent of Net Asset Value 95.10%
Fidelity Advisor Financials Fund - Class I | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Advisor Financials Fund - Class I | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Financials Fund - Class I | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class I | GrandCaymanUKOverseasTerMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class I | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Financials Fund - Class I | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Financials Fund - Class I | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.70%
Fidelity Advisor Financials Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Financials Fund - Class C | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Financials Fund - Class C | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.00%
Fidelity Advisor Financials Fund - Class C | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
Fidelity Advisor Financials Fund - Class C | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
Fidelity Advisor Financials Fund - Class C | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Advisor Financials Fund - Class C | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Financials Fund - Class C | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Financials Fund - Class C | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
Fidelity Advisor Financials Fund - Class C | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Financials Fund - Class C | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Fidelity Advisor Financials Fund - Class C | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.00%
Fidelity Advisor Financials Fund - Class C | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 28.40%
Fidelity Advisor Financials Fund - Class C | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 17.20%
Fidelity Advisor Financials Fund - Class C | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.60%
Fidelity Advisor Financials Fund - Class C | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Financials Fund - Class C | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Financials Fund - Class C | United States  
Holdings [Line Items]  
Percent of Net Asset Value 95.10%
Fidelity Advisor Financials Fund - Class C | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Advisor Financials Fund - Class C | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Financials Fund - Class C | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class C | GrandCaymanUKOverseasTerMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class C | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Financials Fund - Class C | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Financials Fund - Class C | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.70%
Fidelity Advisor Financials Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Financials Fund - Class A | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Fidelity Advisor Financials Fund - Class A | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.00%
Fidelity Advisor Financials Fund - Class A | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.70%
Fidelity Advisor Financials Fund - Class A | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.70%
Fidelity Advisor Financials Fund - Class A | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Advisor Financials Fund - Class A | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Financials Fund - Class A | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Financials Fund - Class A | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.60%
Fidelity Advisor Financials Fund - Class A | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Fidelity Advisor Financials Fund - Class A | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.40%
Fidelity Advisor Financials Fund - Class A | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.00%
Fidelity Advisor Financials Fund - Class A | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 28.40%
Fidelity Advisor Financials Fund - Class A | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 17.20%
Fidelity Advisor Financials Fund - Class A | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.60%
Fidelity Advisor Financials Fund - Class A | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Fidelity Advisor Financials Fund - Class A | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Financials Fund - Class A | United States  
Holdings [Line Items]  
Percent of Net Asset Value 95.10%
Fidelity Advisor Financials Fund - Class A | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Advisor Financials Fund - Class A | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Financials Fund - Class A | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class A | GrandCaymanUKOverseasTerMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.70%
Fidelity Advisor Financials Fund - Class A | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Financials Fund - Class A | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.50%
Fidelity Advisor Financials Fund - Class A | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.70%
Fidelity Advisor Financials Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class Z | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity Advisor Biotechnology Fund - Class Z | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Advisor Biotechnology Fund - Class Z | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Biotechnology Fund - Class Z | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Biotechnology Fund - Class Z | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Biotechnology Fund - Class Z | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class Z | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class Z | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class Z | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class Z | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class Z | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 88.40%
Fidelity Advisor Biotechnology Fund - Class Z | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Advisor Biotechnology Fund - Class Z | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class Z | United States  
Holdings [Line Items]  
Percent of Net Asset Value 90.60%
Fidelity Advisor Biotechnology Fund - Class Z | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Fidelity Advisor Biotechnology Fund - Class Z | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Biotechnology Fund - Class Z | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class Z | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class Z | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class Z | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class Z | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class Z | Germany  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Biotechnology Fund - Class Z | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.50%
Fidelity Advisor Biotechnology Fund - Class Z | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Advisor Biotechnology Fund - Class Z | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class Z | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Biotechnology Fund - Class M | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity Advisor Biotechnology Fund - Class M | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Advisor Biotechnology Fund - Class M | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Biotechnology Fund - Class M | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Biotechnology Fund - Class M | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Biotechnology Fund - Class M | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class M | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class M | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class M | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class M | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class M | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 88.40%
Fidelity Advisor Biotechnology Fund - Class M | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Advisor Biotechnology Fund - Class M | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class M | United States  
Holdings [Line Items]  
Percent of Net Asset Value 90.60%
Fidelity Advisor Biotechnology Fund - Class M | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Fidelity Advisor Biotechnology Fund - Class M | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Biotechnology Fund - Class M | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class M | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class M | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class M | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class M | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class M | Germany  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Biotechnology Fund - Class M | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.50%
Fidelity Advisor Biotechnology Fund - Class M | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Advisor Biotechnology Fund - Class M | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class M | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Biotechnology Fund - Class I | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity Advisor Biotechnology Fund - Class I | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Advisor Biotechnology Fund - Class I | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Biotechnology Fund - Class I | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Biotechnology Fund - Class I | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Biotechnology Fund - Class I | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class I | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class I | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class I | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class I | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class I | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 88.40%
Fidelity Advisor Biotechnology Fund - Class I | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Advisor Biotechnology Fund - Class I | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class I | United States  
Holdings [Line Items]  
Percent of Net Asset Value 90.60%
Fidelity Advisor Biotechnology Fund - Class I | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Fidelity Advisor Biotechnology Fund - Class I | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Biotechnology Fund - Class I | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class I | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class I | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class I | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class I | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class I | Germany  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Biotechnology Fund - Class I | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.50%
Fidelity Advisor Biotechnology Fund - Class I | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Advisor Biotechnology Fund - Class I | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class I | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Biotechnology Fund - Class C | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity Advisor Biotechnology Fund - Class C | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Advisor Biotechnology Fund - Class C | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Biotechnology Fund - Class C | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Biotechnology Fund - Class C | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Biotechnology Fund - Class C | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class C | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class C | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class C | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class C | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class C | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 88.40%
Fidelity Advisor Biotechnology Fund - Class C | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Advisor Biotechnology Fund - Class C | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class C | United States  
Holdings [Line Items]  
Percent of Net Asset Value 90.60%
Fidelity Advisor Biotechnology Fund - Class C | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Fidelity Advisor Biotechnology Fund - Class C | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Biotechnology Fund - Class C | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class C | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class C | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class C | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class C | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class C | Germany  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Biotechnology Fund - Class C | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.50%
Fidelity Advisor Biotechnology Fund - Class C | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Advisor Biotechnology Fund - Class C | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class C | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Biotechnology Fund - Class A | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity Advisor Biotechnology Fund - Class A | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Advisor Biotechnology Fund - Class A | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Biotechnology Fund - Class A | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Biotechnology Fund - Class A | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity Advisor Biotechnology Fund - Class A | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class A | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Fidelity Advisor Biotechnology Fund - Class A | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class A | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class A | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class A | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 88.40%
Fidelity Advisor Biotechnology Fund - Class A | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Advisor Biotechnology Fund - Class A | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class A | United States  
Holdings [Line Items]  
Percent of Net Asset Value 90.60%
Fidelity Advisor Biotechnology Fund - Class A | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%
Fidelity Advisor Biotechnology Fund - Class A | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity Advisor Biotechnology Fund - Class A | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Biotechnology Fund - Class A | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class A | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class A | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity Advisor Biotechnology Fund - Class A | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Biotechnology Fund - Class A | Germany  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Biotechnology Fund - Class A | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.50%
Fidelity Advisor Biotechnology Fund - Class A | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Advisor Biotechnology Fund - Class A | AAPreferredSecuritiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Biotechnology Fund - Class A | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Biotechnology Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Select Industrials Portfolio | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
Select Industrials Portfolio | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Select Industrials Portfolio | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Select Industrials Portfolio | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.60%
Select Industrials Portfolio | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
Select Industrials Portfolio | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.40%
Select Industrials Portfolio | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Select Industrials Portfolio | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Select Industrials Portfolio | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Select Industrials Portfolio | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Select Industrials Portfolio | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 30.90%
Select Industrials Portfolio | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.30%
Select Industrials Portfolio | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Select Industrials Portfolio | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.80%
Select Industrials Portfolio | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Select Industrials Portfolio | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Select Industrials Portfolio | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
Select Industrials Portfolio | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Select Industrials Portfolio | TI8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Select Industrials Portfolio | TI9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.50%
Select Industrials Portfolio | United States  
Holdings [Line Items]  
Percent of Net Asset Value 100.00%
Select Industrials Portfolio | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 98.70%
Select Industrials Portfolio | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class Z | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity Advisor Health Care Fund - Class Z | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity Advisor Health Care Fund - Class Z | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Health Care Fund - Class Z | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Health Care Fund - Class Z | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Health Care Fund - Class Z | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Health Care Fund - Class Z | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class Z | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class Z | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class Z | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class Z | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 37.80%
Fidelity Advisor Health Care Fund - Class Z | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity Advisor Health Care Fund - Class Z | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
Fidelity Advisor Health Care Fund - Class Z | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Fidelity Advisor Health Care Fund - Class Z | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Health Care Fund - Class Z | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Health Care Fund - Class Z | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class Z | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class Z | United States  
Holdings [Line Items]  
Percent of Net Asset Value 91.50%
Fidelity Advisor Health Care Fund - Class Z | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Health Care Fund - Class Z | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class Z | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Health Care Fund - Class Z | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Health Care Fund - Class Z | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class Z | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Health Care Fund - Class Z | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class Z | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class Z | China  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Health Care Fund - Class Z | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.30%
Fidelity Advisor Health Care Fund - Class Z | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class Z | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Health Care Fund - Class M | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity Advisor Health Care Fund - Class M | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity Advisor Health Care Fund - Class M | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Health Care Fund - Class M | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Health Care Fund - Class M | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Health Care Fund - Class M | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Health Care Fund - Class M | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class M | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class M | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class M | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class M | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 37.80%
Fidelity Advisor Health Care Fund - Class M | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity Advisor Health Care Fund - Class M | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
Fidelity Advisor Health Care Fund - Class M | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Fidelity Advisor Health Care Fund - Class M | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Health Care Fund - Class M | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Health Care Fund - Class M | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class M | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class M | United States  
Holdings [Line Items]  
Percent of Net Asset Value 91.50%
Fidelity Advisor Health Care Fund - Class M | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Health Care Fund - Class M | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class M | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Health Care Fund - Class M | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Health Care Fund - Class M | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class M | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Health Care Fund - Class M | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class M | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class M | China  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Health Care Fund - Class M | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.30%
Fidelity Advisor Health Care Fund - Class M | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class M | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Health Care Fund - Class I | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity Advisor Health Care Fund - Class I | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity Advisor Health Care Fund - Class I | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Health Care Fund - Class I | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Health Care Fund - Class I | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Health Care Fund - Class I | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Health Care Fund - Class I | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class I | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class I | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class I | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class I | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 37.80%
Fidelity Advisor Health Care Fund - Class I | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity Advisor Health Care Fund - Class I | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
Fidelity Advisor Health Care Fund - Class I | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Fidelity Advisor Health Care Fund - Class I | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Health Care Fund - Class I | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Health Care Fund - Class I | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class I | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class I | United States  
Holdings [Line Items]  
Percent of Net Asset Value 91.50%
Fidelity Advisor Health Care Fund - Class I | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Health Care Fund - Class I | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class I | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Health Care Fund - Class I | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Health Care Fund - Class I | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class I | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Health Care Fund - Class I | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class I | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class I | China  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Health Care Fund - Class I | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.30%
Fidelity Advisor Health Care Fund - Class I | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class I | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Health Care Fund - Class C | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity Advisor Health Care Fund - Class C | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity Advisor Health Care Fund - Class C | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Health Care Fund - Class C | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Health Care Fund - Class C | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Health Care Fund - Class C | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Health Care Fund - Class C | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class C | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class C | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class C | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class C | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 37.80%
Fidelity Advisor Health Care Fund - Class C | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity Advisor Health Care Fund - Class C | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
Fidelity Advisor Health Care Fund - Class C | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Fidelity Advisor Health Care Fund - Class C | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Health Care Fund - Class C | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Health Care Fund - Class C | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class C | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class C | United States  
Holdings [Line Items]  
Percent of Net Asset Value 91.50%
Fidelity Advisor Health Care Fund - Class C | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Health Care Fund - Class C | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class C | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Health Care Fund - Class C | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Health Care Fund - Class C | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class C | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Health Care Fund - Class C | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class C | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class C | China  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Health Care Fund - Class C | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.30%
Fidelity Advisor Health Care Fund - Class C | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class C | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%
Fidelity Advisor Health Care Fund - Class A | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity Advisor Health Care Fund - Class A | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity Advisor Health Care Fund - Class A | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Health Care Fund - Class A | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Advisor Health Care Fund - Class A | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.80%
Fidelity Advisor Health Care Fund - Class A | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
Fidelity Advisor Health Care Fund - Class A | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class A | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class A | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class A | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class A | TI0Member  
Holdings [Line Items]  
Percent of Net Asset Value 37.80%
Fidelity Advisor Health Care Fund - Class A | TI1Member  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity Advisor Health Care Fund - Class A | TI2Member  
Holdings [Line Items]  
Percent of Net Asset Value 23.40%
Fidelity Advisor Health Care Fund - Class A | TI3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.00%
Fidelity Advisor Health Care Fund - Class A | TI4Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Health Care Fund - Class A | TI5Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity Advisor Health Care Fund - Class A | TI6Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class A | TI7Member  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class A | United States  
Holdings [Line Items]  
Percent of Net Asset Value 91.50%
Fidelity Advisor Health Care Fund - Class A | Netherlands  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
Fidelity Advisor Health Care Fund - Class A | Israel  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class A | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.90%
Fidelity Advisor Health Care Fund - Class A | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Advisor Health Care Fund - Class A | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Advisor Health Care Fund - Class A | France  
Holdings [Line Items]  
Percent of Net Asset Value 0.80%
Fidelity Advisor Health Care Fund - Class A | Denmark  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Advisor Health Care Fund - Class A | Belgium  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Health Care Fund - Class A | China  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Advisor Health Care Fund - Class A | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 97.30%
Fidelity Advisor Health Care Fund - Class A | AAPreferredStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Advisor Health Care Fund - Class A | AABondsMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Health Care Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.40%