State Street Real Estate Securities VIS Fund Performance Management - State Street Real Estate Securities VIS Fund |
Dec. 31, 2025 |
|---|---|
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | <span style="color:#000000;font-family:Arial;font-size:10.02pt;font-weight:bold;">Performance</span> |
| Performance Narrative [Text Block] | The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with that of (i) a broad measure of market performance and (ii) an additional index that SSGA FM believes more closely reflects the market segment(s) in which the Fund invests. The Fund's past performance does not necessarily indicate how the Fund will perform in the future.The bar chart and average annual total returns table do not reflect the fees or charges imposed by the Accounts of the life insurance companies through which shares of the Fund may be purchased. If these fees and charges were included, returns would be lower than those shown. Current performance information for the Fund is available toll free by calling(800)-242-0134 or by visiting our website at www.statestreet.com/im. |
| Performance Past Does Not Indicate Future [Text] | <span style="font-family:Arial;font-size:10.02pt;">The Fund's past performance does not necessarily</span><span style="font-family:Arial;font-size:10.02pt;margin-left:0%;"> indicate how the Fund will perform in the future.</span> |
| Performance Information Illustrates Variability of Returns [Text] | <span style="font-family:Arial;font-size:10.02pt;margin-left:0%;">The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with that of (i) a broad measure of market performance and (ii) an additional index that SSGA FM believes more closely reflects the market segment(s) in which the Fund invests. </span> |
| Bar Chart [Heading] | <span style="color:#000000;font-family:Arial;font-size:10.02pt;font-weight:bold;">Annual Total Returns </span><span style="color:#000000;font-family:Arial;font-size:9.02pt;">(years ended 12/31)</span> |
| Bar Chart Closing [Text Block] | ReturnsQuarter/YearHighest Quarterly Return16.90%Q3 2024Lowest Quarterly Return-24.92%Q1 2020 |
| Performance Table Heading | <span style="font-family:Arial;font-size:10.02pt;font-weight:bold;">Average Annual Total Returns </span><span style="font-family:Arial;font-size:9.02pt;">(for periods ended 12/31/25)</span> |
| Performance Availability Website Address [Text] | <span style="font-family:Arial;font-size:10.02pt;">www.statestreet.com/im</span> |
| Performance Availability Phone [Text] | <span style="font-family:Arial;font-size:10.02pt;">(800)-242-0134</span> |
| Class 1 | |
| Prospectus [Line Items] | |
| Highest Quarterly Return, Label [Optional Text] | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;margin-left:0.0pt;">Highest Quarterly Return</span> |
| Highest Quarterly Return | 16.90% |
| Highest Quarterly Return, Date | Sep. 30, 2024 |
| Lowest Quarterly Return, Label [Optional Text] | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;margin-left:0.0pt;">Lowest Quarterly Return</span> |
| Lowest Quarterly Return | (24.92%) |
| Lowest Quarterly Return, Date | Mar. 31, 2020 |