Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	JOHN HANCOCK VARIABLE INSURANCE TRUST
Prospectus Date	rr_ProspectusDate	Apr. 28, 2025
Small Company Value Trust
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:24pt;">Small Company Value Trust</span>
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Investment objective</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	To seek long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Fees and expenses</span>
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the fund. The fees and expenses do not reflect fees and expenses of any variable insurance or variable annuities contract that may use the fund as its underlying investment option and would be higher if they did.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	<span style="font-family:Arial Narrow;font-size:8pt;font-weight:bold;margin-left:0.0pt;">Annual fund operating expenses (%) </span><span style="font-family:Arial Narrow;font-size:8pt;margin-left:0.0pt;">(expenses that you pay each year as a percentage of the value of your investment)</span>
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	<span style="font-family:Arial Narrow;font-size:8pt;">July 31, 2026</span>
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Portfolio turnover</span>
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During its most recent fiscal year, the fund’s portfolio turnover rate was 32% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	32.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Expense example</span>
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The examples are intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The examples assume that $10,000 is invested in the fund for the periods indicated and then all shares are redeemed at the end of those periods. The examples also assume that the investment has a 5% return each year and that the fund’s operating expenses remain the same. The expense example does not reflect fees and expenses of any variable insurance contract that may use the fund as its underlying investment option and would be higher if they did. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Principal investment strategies</span>
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal market conditions, the fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in companies with market capitalizations, at the time of investment, that do not exceed the maximum market capitalization of any security in the Russell 2000 Index ($15.1 million to $14.3 billion as of February 28, 2025). (The fund will provide written notice to shareholders at least 60 days prior to a change in its 80% investment policy.) The fund invests in small companies whose common stocks are believed to be undervalued. The market capitalization of the companies in the fund’s portfolio and the Russell 2000 Index changes over time, and the fund will not sell a stock just because the company has grown to a market capitalization outside the range. The fund may, on occasion, purchase companies with a market capitalization above the range. Reflecting a value approach to investing, the fund will seek the stocks of companies whose current stock prices do not appear to adequately reflect their underlying value as measured by assets, earnings, cash flow, or business franchises. The subadvisor’s in house research team seeks to identify companies that appear to be undervalued by various measures, and may be temporarily out of favor, but have good prospects for capital appreciation. In selecting investments, they generally look for some of the following factors: ●Low price/earnings, price/book value, or price/cash flow ratios relative to the Russell 2000 Index, a company’s peers, or company’s historical norm; ●Low stock price relative to a company’s underlying asset values; ●Above-average dividend yield relative to a company’s peers or its own historic norm; ●A plan to improve the business through restructuring; and/or ●A sound balance sheet and other positive financial characteristics. ●Price/earnings ratio - Dividing a stock’s price by its earnings per share generates a price/earnings or P/E ratio. A stock with a P/E ratio that is significantly below that of its peers, the market as a whole, or its own historical norm may represent an attractive opportunity. ●Price/book value ratio - Dividing a stock’s price by its book value per share indicates how a stock is priced relative to the accounting (i.e., book) value of the company’s assets. A ratio below the market, that of its competitors, or its own historical norm could indicate a stock that is undervalued. ●Dividend yield - A stock’s dividend yield is found by dividing its annual dividend by its share price. A yield significantly above a stock’s own historical norm or that of its peers may suggest an investment opportunity. A stock selling at $10 with an annual dividend of $0.50 has a 5% yield. ●Price/cash flow - Dividing a stock’s price by the company’s cash flow per share, rather than by its earnings or book value, provides a more useful measure of value in some cases. A ratio below that of the market or a company’s peers suggests the market may be incorrectly valuing the company’s cash flow for reasons that could be temporary. ●Undervalued assets - This analysis compares a company’s stock price with its underlying asset values, its projected value in the private (as opposed to public) market, or its expected value if the company or parts of it were sold or liquidated. ●Restructuring opportunities - Many well-established companies experience business challenges that can lead to a temporary decline in their financial performance. These challenges can include a poorly integrated acquisition, difficulties in product manufacturing or distribution, a downturn in a major end market, or an increase in industry capacity that negatively affects pricing. The shares of such companies frequently trade at depressed valuations. These companies can become successful investments if their management is sufficiently skilled and motivated to properly restructure the organization, their financial flexibility is adequate, the underlying value of the business has not been impaired, or their business environment improves or remains healthy. While most assets will be invested in U.S. common stocks, including real estate investment trusts (REITs) that pool money to invest in properties and mortgages, the fund may purchase other securities, including foreign securities (up to 20% of its total net assets), futures, and options. The fund may invest in fixed-income and convertible securities without restrictions on quality or rating, including up to 10% of total assets in below-investment-grade fixed-income securities (“junk bonds”) and loans. The fund’s fixed-income investments may include privately negotiated notes or loans, including loan participations and assignments (“bank loans”). These investments in bank loans will be made only in companies, municipalities or entities that meet the fund’s investment criteria. Direct investments in bank loans may be illiquid and holding a loan could expose the fund to the risks of being a direct lender. Since the fund invests primarily in equity securities, the risks associated with fixed-income securities will not affect the fund as much as they would a fund that invests more of its assets in fixed-income securities. The fund holds a certain portion of its assets in money market reserves, which can consist of shares of certain T. Rowe Price money market funds as well as U.S. dollar and foreign currency-denominated money market securities, including repurchase agreements, in the two highest rating categories, maturing in one year or less. The fund may sell securities for a variety of reasons, including to realize gains, limit losses or redeploy assets into more promising opportunities. The fund may invest up to 10% of its total assets in hybrid instruments. Hybrid instruments are a type of high-risk derivatives which can combine the characteristics of securities, futures and options. Such securities may bear interest or pay dividends at below (or even relatively nominal) rates. The fund may focus its investments in a particular sector or sectors of the economy.
Risk [Heading]	rr_RiskHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Principal risks</span>
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Past performance</span>
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following information illustrates the variability of the fund’s returns and provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual returns compared with a broad-based securities market index.Past performance does not indicate future results. The Russell 2000 Value Index shows how the fund’s performance compares against the returns of similar investments. All figures assume dividend reinvestment. The performance information below does not reflect fees and expenses of any variable insurance contract which may use JHVIT as its underlying investment option. If such fees and expenses had been reflected, performance would be lower.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	<span style="font-family:Arial Narrow;font-size:9pt;">The following information illustrates the variability of the fund’s returns and provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual returns compared with a broad-based securities market index.</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="font-family:Arial Narrow;font-size:9pt;">Past performance does not indicate future results.</span>
Bar Chart [Heading]	rr_BarChartHeading	<span style="font-family:Arial Narrow;font-size:9pt;font-weight:bold;">Calendar year total returns (%)—Series I</span>
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best quarter:Q4 202028.47%Worst quarter:Q1 2020-31.27%
Performance Table Heading	rr_PerformanceTableHeading	<span style="font-family:Arial Narrow;font-size:8pt;font-weight:bold;margin-left:0.0pt;">Average annual total returns (%)—as of 12/31/2024</span>
Performance Table Market Index Changed	rr_PerformanceTableMarketIndexChanged	<span style="font-family:Arial Narrow;font-size:8pt;">The fund has designated the Russell 3000 Index as its new broad-based securities market index in accordance with the revised definition for such an index.</span>
Small Company Value Trust | Risk Lose Money [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Many factors affect performance, and fund shares will fluctuate in price, meaning you could lose money.
Small Company Value Trust | Risk Not Insured Depository Institution [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Small Company Value Trust | Cash And Cash Equivalents Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Cash and cash equivalents risk.  Under certain market conditions, such as during a rising stock market, rising interest rate or rising credit spread markets, the use of cash and/or cash equivalents, including money market instruments, could have a negative effect on the fund’s ability to achieve its investment objective and may negatively impact the fund’s performance.
Small Company Value Trust | Convertible Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Convertible securities risk.  Convertible securities are subject to certain risks of both equity and debt securities. The market values of convertible securities tend to fall as interest rates rise and rise as interest rates fall. As the market price of underlying common stock declines below the conversion price, the market value of the convertible security tends to be increasingly influenced by its yield.
Small Company Value Trust | Credit And Counterparty Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Credit and counterparty risk.  The issuer or guarantor of a fixed-income security, the counterparty to an over-the-counter derivatives contract, or a borrower of fund securities may not make timely payments or otherwise honor its obligations. A downgrade or default affecting any of the fund’s securities could affect the fund’s performance.
Small Company Value Trust | Economic And Market Events Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Economic and market events risk.  Events in the U.S. and global financial markets, including actions taken by the U.S. Federal Reserve or foreign central banks to stimulate or stabilize economic growth, may at times result in unusually high market volatility, which could negatively impact performance. Reduced liquidity in credit and fixed-income markets could adversely affect issuers worldwide. Banks and financial services companies could suffer losses if interest rates rise or economic conditions deteriorate.
Small Company Value Trust | Equity Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Equity securities risk.  The price of equity securities may decline due to changes in a company’s financial condition or overall market conditions. Securities the manager believes are undervalued may never realize their full potential value, and in certain markets value stocks may underperform the market as a whole.
Small Company Value Trust | Financial Services Sector Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Financial services sector risk.  Financial services companies can be significantly affected by economic, market, and business developments, borrowing costs, interest-rate fluctuations, competition, and government regulation, among other factors.
Small Company Value Trust | Fixed Income Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Fixed-income securities risk.  A rise in interest rates typically causes bond prices to fall. The longer the average maturity or duration of the bonds held by a fund, the more sensitive it will likely be to interest-rate fluctuations. An issuer may not make all interest payments or repay all or any of the principal borrowed. Changes in a security’s credit quality may adversely affect fund performance.
Small Company Value Trust | Foreign Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Foreign securities risk.  Less information may be publicly available regarding foreign issuers, including foreign government issuers. Foreign securities may be subject to foreign taxes and may be more volatile than U.S. securities. Currency fluctuations and political and economic developments may adversely impact the value of foreign securities.
Small Company Value Trust | Hedging Derivatives And Other Strategic Transactions Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Hedging, derivatives, and other strategic transactions risk.  Hedging, derivatives, and other strategic transactions may increase a fund’s volatility and could produce disproportionate losses, potentially more than the fund’s principal investment. Risks of these transactions are different from and possibly greater than risks of investing directly in securities and other traditional instruments. Under certain market conditions, derivatives could become harder to value or sell and may become subject to liquidity risk (i.e., the inability to enter into closing transactions). Derivatives and other strategic transactions that the fund intends to utilize include: futures contracts and options. Futures contracts and options generally are subject to counterparty risk.
Small Company Value Trust | Hybrid Instrument Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Hybrid instrument risk.  Hybrid instruments (a type of potentially high-risk derivative) combine the elements of futures contracts or options with those of debt, preferred equity or a depository instrument. Hybrid instruments entail greater market risk and may be more volatile than traditional debt instruments, may bear interest or pay preferred dividends at below-market rates, and may be illiquid. The risks of investing in hybrid instruments are a combination of the risks of investing in securities, options, futures, and currencies.
Small Company Value Trust | Illiquid And Restricted Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Illiquid and restricted securities risk.  Illiquid and restricted securities may be difficult to value and may involve greater risks than liquid securities. Illiquidity may have an adverse impact on a particular security’s market price and the fund’s ability to sell the security.
Small Company Value Trust | Investment Company Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Investment company securities risk.  Fund shareholders indirectly bear their proportionate share of the expenses of any investment company in which the fund invests. The total return on such investments will be reduced by the operating expenses and fees of such other investment companies, including advisory fees.
Small Company Value Trust | Liquidity Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Liquidity risk.  The extent (if at all) to which a security may be sold or a derivative position closed without negatively impacting its market value may be impaired by reduced market activity or participation, legal restrictions, or other economic and market impediments. Liquidity risk may be magnified in rising interest rate environments due to higher than normal redemption rates. Widespread selling of fixed-income securities to satisfy redemptions during periods of reduced demand may adversely impact the price or salability of such securities. Periods of heavy redemption could cause the fund to sell assets at a loss or depressed value, which could negatively affect performance. Redemption risk is heightened during periods of declining or illiquid markets.
Small Company Value Trust | Loan Participations Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Loan participations risk.  Participations and assignments involve special types of risks, including credit risk, interest-rate risk, counterparty risk, liquidity risk, risks associated with extended settlement, and the risks of being a lender.
Small Company Value Trust | Lower Rated And High Yield Fixed Income Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Lower-rated and high-yield fixed-income securities risk.  Lower-rated and high-yield fixed-income securities (junk bonds) are subject to greater credit quality risk, risk of default, and price volatility than higher-rated fixed-income securities, may be considered speculative, and can be difficult to resell.
Small Company Value Trust | Operational And Cybersecurity Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Operational and cybersecurity risk.  Cybersecurity breaches may allow an unauthorized party to gain access to fund assets, customer data, or proprietary information, or cause a fund or its service providers to suffer data corruption or lose operational functionality. Similar incidents affecting issuers of a fund’s securities may negatively impact performance. Operational risk may arise from human error, error by third parties, communication errors, or technology failures, among other causes.
Small Company Value Trust | Real Estate Investment Trust Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Real estate investment trust (REIT) risk.  REITs, pooled investment vehicles that typically invest in real estate directly or in loans collateralized by real estate, carry risks associated with owning real estate, including the potential for a decline in value due to economic or market conditions.
Small Company Value Trust | Real Estate Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Real estate securities risk.  Securities of companies in the real estate industry carry risks associated with owning real estate, including the potential for a decline in value due to economic or market conditions.
Small Company Value Trust | Repurchase Agreement Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Repurchase agreements risk.  The risk of a repurchase agreement transaction is limited to the ability of the seller to pay the agreed-upon sum on the delivery date. In the event of bankruptcy or other default by the seller, the instrument purchased may decline in value, interest payable on the instrument may be lost and there may be possible difficulties and delays in obtaining collateral and delays and expense in liquidating the instrument.
Small Company Value Trust | Sector Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Sector risk.  When a fund focuses its investments in certain sectors of the economy, its performance may be driven largely by sector performance and could fluctuate more widely than if the fund were invested more evenly across sectors. To the extent that a fund invests in securities of companies in the financial services sector, the fund may be significantly affected by economic, market, and business developments, borrowing costs, interest-rate fluctuations, competition, and government regulation, among other factors, impacting that sector.
Small Company Value Trust | Small And Mid Sized Company Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Small and mid-sized company risk.  Small and mid-sized companies are generally less established and may be more volatile than larger companies. Small and/or mid-capitalization securities may underperform the market as a whole.
Small Company Value Trust | Value Investment Style Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Value investment style risk.  Value securities may underperform the market as a whole, which may cause value-oriented funds to underperform equity funds with other investment strategies. Securities the manager believes are undervalued may never perform as expected.
Small Company Value Trust | Series I
Risk Return Abstract	rr_RiskReturnAbstract
Management fee	rr_ManagementFeesOverAssets	1.05%
Distribution and service (Rule 12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.05%
Other expenses	rr_OtherExpensesOverAssets	0.10%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.20%
Contractual expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.01%)	[1]
Total annual fund operating expenses after expense reimbursements	rr_NetExpensesOverAssets	1.19%
1 year	rr_ExpenseExampleYear01	$ 121
3 years	rr_ExpenseExampleYear03	380
5 years	rr_ExpenseExampleYear05	659
10 years	rr_ExpenseExampleYear10	$ 1,454
2015	rr_AnnualReturn2015	(5.60%)
2016	rr_AnnualReturn2016	32.32%
2017	rr_AnnualReturn2017	11.49%
2018	rr_AnnualReturn2018	(12.94%)
2019	rr_AnnualReturn2019	25.53%
2020	rr_AnnualReturn2020	9.24%
2021	rr_AnnualReturn2021	22.70%
2022	rr_AnnualReturn2022	(18.73%)
2023	rr_AnnualReturn2023	13.49%
2024	rr_AnnualReturn2024	10.20%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	<span style="color:#000000;font-family:Arial Narrow;font-size:8pt;font-weight:bold;margin-left:0.0pt;">Best quarter:</span>
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	28.47%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	<span style="color:#000000;font-family:Arial Narrow;font-size:8pt;font-weight:bold;margin-left:0.0pt;">Worst quarter:</span>
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(31.27%)
1 year	rr_AverageAnnualReturnYear01	10.20%
5 year	rr_AverageAnnualReturnYear05	6.38%
10 year	rr_AverageAnnualReturnYear10	7.56%
Small Company Value Trust | Series II
Risk Return Abstract	rr_RiskReturnAbstract
Management fee	rr_ManagementFeesOverAssets	1.05%
Distribution and service (Rule 12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.10%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.40%
Contractual expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.01%)	[1]
Total annual fund operating expenses after expense reimbursements	rr_NetExpensesOverAssets	1.39%
1 year	rr_ExpenseExampleYear01	$ 142
3 years	rr_ExpenseExampleYear03	442
5 years	rr_ExpenseExampleYear05	765
10 years	rr_ExpenseExampleYear10	$ 1,679
1 year	rr_AverageAnnualReturnYear01	9.88%
5 year	rr_AverageAnnualReturnYear05	6.17%
10 year	rr_AverageAnnualReturnYear10	7.35%
Small Company Value Trust | NAV
Risk Return Abstract	rr_RiskReturnAbstract
Management fee	rr_ManagementFeesOverAssets	1.05%
Distribution and service (Rule 12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.10%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.15%
Contractual expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.01%)	[1]
Total annual fund operating expenses after expense reimbursements	rr_NetExpensesOverAssets	1.14%
1 year	rr_ExpenseExampleYear01	$ 116
3 years	rr_ExpenseExampleYear03	364
5 years	rr_ExpenseExampleYear05	632
10 years	rr_ExpenseExampleYear10	$ 1,397
1 year	rr_AverageAnnualReturnYear01	10.32%
5 year	rr_AverageAnnualReturnYear05	6.44%
10 year	rr_AverageAnnualReturnYear10	7.63%
Small Company Value Trust | Russell 3000 Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	23.81%	[2]
5 year	rr_AverageAnnualReturnYear05	13.86%	[2]
10 year	rr_AverageAnnualReturnYear10	12.55%	[2]
Small Company Value Trust | Russell 2000 Value Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	8.05%
5 year	rr_AverageAnnualReturnYear05	7.29%
10 year	rr_AverageAnnualReturnYear10	7.14%

[1] The advisor contractually agrees to waive a portion of its management fee and/or reimburse expenses for the fund and certain other John Hancock funds according to an asset level breakpoint schedule that is based on the aggregate net assets of all the funds participating in the waiver or reimbursement, including the fund (the participating portfolios). This waiver equals, on an annualized basis, 0.0100% of that portion of the aggregate net assets of all the participating portfolios that exceeds $75 billion but is less than or equal to $125 billion; 0.0125% of that portion of the aggregate net assets of all the participating portfolios that exceeds $125 billion but is less than or equal to $150 billion; 0.0150% of that portion of the aggregate net assets of all the participating portfolios that exceeds $150 billion but is less than or equal to $175 billion; 0.0175% of that portion of the aggregate net assets of all the participating portfolios that exceeds $175 billion but is less than or equal to $200 billion; 0.0200% of that portion of the aggregate net assets of all the participating portfolios that exceeds $200 billion but is less than or equal to $225 billion; and 0.0225% of that portion of the aggregate net assets of all the participating portfolios that exceeds $225 billion. The amount of the reimbursement is calculated daily and allocated among all the participating portfolios in proportion to the daily net assets of each participating portfolio. During its most recent fiscal year, the fund’s reimbursement amounted to 0.01% of the fund’s average daily net assets. This agreement expires on July 31, 2026, unless renewed by mutual agreement of the fund and the advisor based upon a determination that this is appropriate under the circumstances at that time.

[2] The fund has designated the Russell 3000 Index as its new broad-based securities market index in accordance with the revised definition for such an index.