JPMorgan Core Bond Portfolio Investment Risks - JPMorgan Core Bond Portfolio	Dec. 31, 2025
Market Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Market Risk. The Portfolio’s share price can fall because of, among other things, a decline in the market as a whole, deterioration in the prospects for a particular industry or company, changes in general economic conditions, such as prevailing interest rates or investor sentiment, or other factors including terrorism, war, natural disasters and the spread of infectious illness including epidemics or pandemics. In addition, unexpected political, regulatory, trade and diplomatic events within the United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Significant disruptions to the financial markets could adversely affect the liquidity and volatility of securities held by the Portfolio.
Interest Rate Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Interest Rate Risk. The value of the Portfolio’s investments in fixed income securities may decline when prevailing interest rates rise or increase when interest rates fall. The longer a security’s maturity or duration, the greater its value will change in response to changes in interest rates. The interest earned on the Portfolio’s investments in fixed income securities may decline when prevailing interest rates fall. During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns or pay dividends to Portfolio shareholders. Additionally, under certain market conditions in which interest rates are low or negative, the Portfolio may have a very low, or even negative yield. A low or negative yield would cause the Portfolio to lose money and the net asset value of the Portfolio’s shares to decline in certain conditions and over certain time periods. Changes in prevailing interest rates, particularly sudden changes, may also increase the level of volatility in fixed income and other markets, increase redemptions in the Portfolio’s shares and reduce the liquidity of the Portfolio’s debt securities and other income-producing holdings. Changes in interest rate levels are caused by a variety of factors, such as central bank monetary policies, inflation rates, and general economic and market conditions.
Credit and Counterparty Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Credit and Counterparty Risk. The value of the Portfolio’s investments may be adversely affected if a security’s credit rating is downgraded or an issuer of an investment held by the Portfolio fails to pay an obligation on a timely basis, otherwise defaults or is perceived by other investors to be less creditworthy. If a counterparty to a derivatives or other transaction with the Portfolio files for bankruptcy, becomes insolvent, or otherwise becomes unable or unwilling to honor its obligation to the Portfolio, the Portfolio may experience significant losses or delays in realizing income on or recovering collateral and may lose all or a part of the income from the transaction.
Foreign Investment Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Foreign Investment Risk. Investments in foreign securities, whether direct or indirect, tend to be more volatile and less liquid than investments in U.S. securities because, among other things, they involve risks relating to political, social, economic and other developments abroad, as well as risks resulting from differences between the regulations and reporting standards and practices to which U.S. and foreign issuers are subject. To the extent foreign securities are denominated in foreign currencies, their values may be adversely affected by changes in currency exchange rates. All of the risks of investing in foreign securities are typically increased by investing in emerging market countries. To the extent the Portfolio invests in foreign sovereign debt securities, it is subject to additional risks.
Mortgage Backed and Asset Backed Securities Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Mortgage-Backed and Asset-Backed Securities Risk. The value of investments in mortgage-backed and asset-backed securities is subject to interest rate risk and credit and counterparty risk. These securities are also subject to the risk that issuers will prepay the principal more quickly or more slowly than expected, which could cause the Portfolio to invest the proceeds in less attractive investments or increase the volatility of its prices. To the extent mortgage-backed and asset-backed securities held by the Portfolio are backed by lower rated securities, such as sub-prime obligations, or are subordinated to other interests in the same mortgage or asset pool, the likelihood of the Portfolio receiving payments of principal or interest may be substantially limited.
Mortgage Dollar Roll Transactions Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Mortgage Dollar Roll Transactions Risk. Mortgage dollar roll transactions are subject to the risk that the value of the securities the Portfolio is obligated to purchase will decline below the agreed upon purchase price. In addition, the Portfolio will incur higher transaction costs if its mortgage dollar roll transactions lead to higher portfolio turnover. These transactions also may subject the Portfolio to a form of investment leverage, which may increase the Portfolio’s volatility and may require the Portfolio to liquidate portfolio securities when it is not advantageous to do so.
TIPS and Inflation Linked Bonds Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	TIPS and Inflation-Linked Bonds Risk. The value of inflation-protected securities generally fluctuates in response to changes in real interest rates, which are in turn tied to the relationship between nominal interest rates and the rate of inflation. Therefore, if inflation were to rise at a faster rate than nominal interest rates, real interest rates would decline, leading to an increase in the value of inflation-protected securities. In contrast, if nominal interest rates increased at a faster rate than inflation, real interest rates would rise, leading to a decrease in the value of inflation-protected securities. When real interest rates are rising faster than nominal interest rates, inflation-indexed bonds, including Treasury Inflation Protected Securities, may experience greater losses than other fixed income securities with similar durations. The inflation-protected securities markets are generally much smaller and less liquid than the markets for nominal bonds from the same issuers and as such can suffer losses during times of economic stress or illiquidity.
Rule 144A and Other Exempted Securities Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Rule 144A and Other Exempted Securities Risk. In the U.S. market, private placements may typically be sold only to qualified institutional buyers, or qualified purchasers, as applicable. If an insufficient number of eligible buyers is interested in purchasing privately placed and other securities or instruments exempt from Securities and Exchange Commission registration (collectively “private placements”) at a particular time, this could adversely affect the marketability of such investments and the Portfolio might be unable to dispose of them promptly or at reasonable prices, subjecting the Portfolio to liquidity risk. Even the Portfolio’s holdings of liquid private placements may increase the level of Portfolio illiquidity if eligible buyers are unable or unwilling to purchase them at a particular time. The information that issuers of Rule 144A eligible securities are required to disclose to potential investors is much less extensive than that required of public companies and is not publicly available, and issuers of Rule 144A eligible securities can require recipients of the offering information (such as the Portfolio) to agree contractually to keep the information confidential, which could also adversely affect the Portfolio’s ability to dispose of the security.
Risk Lose Money [Member]
Prospectus [Line Items]
Risk [Text Block]	You could lose money by investing in the Portfolio.
Risk Not Insured Depository Institution [Member]
Prospectus [Line Items]
Risk [Text Block]	An investment in the Portfolio through a Contract is not a deposit or obligation of, or guaranteed by, any bank, and is not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. Government.

JPMorgan Core Bond Portfolio Investment Risks - JPMorgan Core Bond Portfolio

Dec. 31, 2025

Market Risk. The Portfolio’s share price can fall because of, among other things, a decline in the market as a whole, deterioration in the prospects for a particular industry or company, changes in general economic conditions, such as prevailing interest rates or investor sentiment, or other factors including terrorism, war, natural disasters and the spread of infectious illness including epidemics or pandemics. In addition, unexpected political, regulatory, trade and diplomatic events within the United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Significant disruptions to the financial markets could adversely affect the liquidity and volatility of securities held by the Portfolio.

Prospectus [Line Items]

Risk [Text Block]

Interest Rate Risk. The value of the Portfolio’s investments in fixed income securities may decline when prevailing interest rates rise or increase when interest rates fall. The longer a security’s maturity or duration, the greater its value will change in response to changes in interest rates. The interest earned on the Portfolio’s investments in fixed income securities may decline when prevailing interest rates fall. During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns or pay dividends to Portfolio shareholders. Additionally, under certain market conditions in which interest rates are low or negative, the Portfolio may have a very low, or even negative yield. A low or negative yield would cause the Portfolio to lose money and the net asset value of the Portfolio’s shares to decline in certain conditions and over certain time periods. Changes in prevailing interest rates, particularly sudden changes, may also increase the level of volatility in fixed income and other markets, increase redemptions in the Portfolio’s shares and reduce the liquidity of the Portfolio’s debt securities and other income-producing holdings. Changes in interest rate levels are caused by a variety of factors, such as central bank monetary policies, inflation rates, and general economic and market conditions.

Credit and Counterparty Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Credit and Counterparty Risk. The value of the Portfolio’s investments may be adversely affected if a security’s credit rating is downgraded or an issuer of an investment held by the Portfolio fails to pay an obligation on a timely basis, otherwise defaults or is perceived by other investors to be less creditworthy. If a counterparty to a derivatives or other transaction with the Portfolio files for bankruptcy, becomes insolvent, or otherwise becomes unable or unwilling to honor its obligation to the Portfolio, the Portfolio may experience significant losses or delays in realizing income on or recovering collateral and may lose all or a part of the income from the transaction.

Foreign Investment Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Foreign Investment Risk. Investments in foreign securities, whether direct or indirect, tend to be more volatile and less liquid than investments in U.S. securities because, among other things, they involve risks relating to political, social, economic and other developments abroad, as well as risks resulting from differences between the regulations and reporting standards and practices to which U.S. and foreign issuers are subject. To the extent foreign securities are denominated in foreign currencies, their values may be adversely affected by changes in currency exchange rates. All of the risks of investing in foreign securities are typically increased by investing in emerging market countries. To the extent the Portfolio invests in foreign sovereign debt securities, it is subject to additional risks.

Mortgage Backed and Asset Backed Securities Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Mortgage-Backed and Asset-Backed Securities Risk. The value of investments in mortgage-backed and asset-backed securities is subject to interest rate risk and credit and counterparty risk. These securities are also subject to the risk that issuers will prepay the principal more quickly or more slowly than expected, which could cause the Portfolio to invest the proceeds in less attractive investments or increase the volatility of its prices. To the extent mortgage-backed and asset-backed securities held by the Portfolio are backed by lower rated securities, such as sub-prime obligations, or are subordinated to other interests in the same mortgage or asset pool, the likelihood of the Portfolio receiving payments of principal or interest may be substantially limited.

Mortgage Dollar Roll Transactions Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Mortgage Dollar Roll Transactions Risk. Mortgage dollar roll transactions are subject to the risk that the value of the securities the Portfolio is obligated to purchase will decline below the agreed upon purchase price. In addition, the Portfolio will incur higher transaction costs if its mortgage dollar roll transactions lead to higher portfolio turnover. These transactions also may subject the Portfolio to a form of investment leverage, which may increase the Portfolio’s volatility and may require the Portfolio to liquidate portfolio securities when it is not advantageous to do so.

TIPS and Inflation Linked Bonds Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

TIPS and Inflation-Linked Bonds Risk. The value of inflation-protected securities generally fluctuates in response to changes in real interest rates, which are in turn tied to the relationship between nominal interest rates and the rate of inflation. Therefore, if inflation were to rise at a faster rate than nominal interest rates, real interest rates would decline, leading to an increase in the value of inflation-protected securities. In contrast, if nominal interest rates increased at a faster rate than inflation, real interest rates would rise, leading to a decrease in the value of inflation-protected securities. When real interest rates are rising faster than nominal interest rates, inflation-indexed bonds, including Treasury Inflation Protected Securities, may experience greater losses than other fixed income securities with similar durations. The inflation-protected securities markets are generally much smaller and less liquid than the markets for nominal bonds from the same issuers and as such can suffer losses during times of economic stress or illiquidity.

Rule 144A and Other Exempted Securities Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Rule 144A and Other Exempted Securities Risk. In the U.S. market, private placements may typically be sold only to qualified institutional buyers, or qualified purchasers, as applicable. If an insufficient number of eligible buyers is interested in purchasing privately placed and other securities or instruments exempt from Securities and Exchange Commission registration (collectively “private placements”) at a particular time, this could adversely affect the marketability of such investments and the Portfolio might be unable to dispose of them promptly or at reasonable prices, subjecting the Portfolio to liquidity risk. Even the Portfolio’s holdings of liquid private placements may increase the level of Portfolio illiquidity if eligible buyers are unable or unwilling to purchase them at a particular time. The information that issuers of Rule 144A eligible securities are required to disclose to potential investors is much less extensive than that required of public companies and is not publicly available, and issuers of Rule 144A eligible securities can require recipients of the offering information (such as the Portfolio) to agree contractually to keep the information confidential, which could also adversely affect the Portfolio’s ability to dispose of the security.

Risk Lose Money [Member]

Prospectus [Line Items]

Risk [Text Block]

You could lose money by investing in the Portfolio.

Risk Not Insured Depository Institution [Member]

Prospectus [Line Items]

Risk [Text Block]

An investment in the Portfolio through a Contract is not a deposit or obligation of, or guaranteed by, any bank, and is not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. Government.