Brighthouse Asset Allocation 100 Portfolio Investment Strategy - Brighthouse Asset Allocation 100 Portfolio	Dec. 31, 2025
Prospectus [Line Items]
Strategy [Heading]	<span style="color:#000000;font-family:Times New Roman;font-size:11.5pt;font-weight:bold;">Principal Investment Strategies</span>
Strategy Narrative [Text Block]	The Portfolio seeks to achieve its objective by investing substantially all of its assets in Class A shares of the Underlying Portfolios, which are portfolios of Brighthouse Funds Trust I (the “Trust”) and Brighthouse Funds Trust II (“Trust II”). The Portfolio has a target allocation between the broad asset classes of equity and fixed income. Brighthouse Investment Advisers, LLC (“BIA” or “Adviser”), the adviser to the Portfolio, establishes specific target investment percentages for the asset classes and the various components of each asset category. BIA determines these target allocations based on a variety of models and factors, including its long-term outlook for the return and risk characteristics of the various asset classes and the relationship between those asset classes. BIA then selects the Underlying Portfolios in which the Portfolio invests based on, among other factors, the Underlying Portfolios’ investment objectives, policies, investment processes and portfolio analytical and management personnel. Under normal circumstances, the Portfolio invests substantially all of its assets in Underlying Portfolios that may hold large cap, small cap, mid cap or foreign equity securities in accordance with target allocations of 100% to equity securities. The following chart describes the target allocations, as of April 27, 2026, to equity securities. You should note that these percentages do not directly correspond to investment in the Underlying Portfolios because each Underlying Portfolio may contain one or more asset classes (e.g., equity and fixed income) and each Underlying Portfolio may contain various subsets of an asset class (e.g., small cap, mid cap and foreign securities). Although the Portfolio’s investments in the Underlying Portfolios will be made in an attempt to achieve the target allocations, the actual allocations may vary from the Portfolio’s target allocations in the chart below. Deviations from the asset class target allocations will affect the asset class subset target allocations. In addition, the Portfolio’s actual allocations could vary substantially from the target allocations due to market valuation changes.Asset ClassTarget AllocationEquity100%U.S. Large Cap44.25%U.S. Mid Cap12.50%U.S. Small Cap8.25%Foreign Equity35%Individual figures may not add up to the totals shown due to rounding. The “Foreign Equity” allocation shown above may be invested in foreign equity securities of any capitalization or country but primarily will be invested in larger capitalization companies of developed countries. The Portfolio seeks to achieve capital growth through its investments in Underlying Portfolios that invest in equity securities. These investments include Underlying Portfolios that invest in stocks of large established U.S. companies, as well as, to a lesser extent, in stocks of foreign companies, including companies in emerging markets, and small U.S. companies with above-average growth potential. Periodically, BIA will evaluate the Portfolio’s allocation between equity and fixed income, inclusive of the exposure to various investment styles and asset sectors, relative to the Portfolio’s risk profile. It is anticipated that any changes to the targets for the broad asset classes will be, in any given year, within a range of plus or minus 10% from the current allocations. Concurrently, BIA will consider whether to make changes to the Portfolio’s investments in any of the Underlying Portfolios. For additional information about the Portfolio’s investment strategies, the names of the Underlying Portfolios in which the Portfolio may invest and where to find more detailed information about the Portfolio’s investments in the Underlying Portfolios, please see “Additional Information about this Portfolio’s Investment Strategies” in the Prospectus.

Brighthouse Asset Allocation 100 Portfolio Investment Strategy - Brighthouse Asset Allocation 100 Portfolio

Dec. 31, 2025

<span style="color:#000000;font-family:Times New Roman;font-size:11.5pt;font-weight:bold;">Principal Investment Strategies</span>

Strategy Narrative [Text Block]

The Portfolio seeks to achieve its objective by investing substantially all of its assets in Class A shares of the Underlying Portfolios, which are portfolios of Brighthouse Funds Trust I (the “Trust”) and Brighthouse Funds Trust II (“Trust II”). The Portfolio has a target allocation between the broad asset classes of equity and fixed income. Brighthouse Investment Advisers, LLC (“BIA” or “Adviser”), the adviser to the Portfolio, establishes specific target investment percentages for the asset classes and the various components of each asset category. BIA determines these target allocations based on a variety of models and factors, including its long-term outlook for the return and risk characteristics of the various asset classes and the relationship between those asset classes. BIA then selects the Underlying Portfolios in which the Portfolio invests based on, among other factors, the Underlying Portfolios’ investment objectives, policies, investment processes and portfolio analytical and management personnel. Under normal circumstances, the Portfolio invests substantially all of its assets in Underlying Portfolios that may hold large cap, small cap, mid cap or foreign equity securities in accordance with target allocations of 100% to equity securities. The following chart describes the target allocations, as of April 27, 2026, to equity securities. You should note that these percentages do not directly correspond to investment in the Underlying Portfolios because each Underlying Portfolio may contain one or more asset classes (e.g., equity and fixed income) and each Underlying Portfolio may contain various subsets of an asset class (e.g., small cap, mid cap and foreign securities). Although the Portfolio’s investments in the Underlying Portfolios will be made in an attempt to achieve the target allocations, the actual allocations may vary from the Portfolio’s target allocations in the chart below. Deviations from the asset class target allocations will affect the asset class subset target allocations. In addition, the Portfolio’s actual allocations could vary substantially from the target allocations due to market valuation changes.Asset ClassTarget Allocation*Equity100%U.S. Large Cap44.25%U.S. Mid Cap12.50%U.S. Small Cap8.25%Foreign Equity35%*Individual figures may not add up to the totals shown due to rounding. The “Foreign Equity” allocation shown above may be invested in foreign equity securities of any capitalization or country but primarily will be invested in larger capitalization companies of developed countries. The Portfolio seeks to achieve capital growth through its investments in Underlying Portfolios that invest in equity securities. These investments include Underlying Portfolios that invest in stocks of large established U.S. companies, as well as, to a lesser extent, in stocks of foreign companies, including companies in emerging markets, and small U.S. companies with above-average growth potential. Periodically, BIA will evaluate the Portfolio’s allocation between equity and fixed income, inclusive of the exposure to various investment styles and asset sectors, relative to the Portfolio’s risk profile. It is anticipated that any changes to the targets for the broad asset classes will be, in any given year, within a range of plus or minus 10% from the current allocations. Concurrently, BIA will consider whether to make changes to the Portfolio’s investments in any of the Underlying Portfolios. For additional information about the Portfolio’s investment strategies, the names of the Underlying Portfolios in which the Portfolio may invest and where to find more detailed information about the Portfolio’s investments in the Underlying Portfolios, please see “Additional Information about this Portfolio’s Investment Strategies” in the Prospectus.