Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	JOHN HANCOCK INVESTMENT TRUST
Prospectus Date	rr_ProspectusDate	Mar. 01, 2025
Class NAV | John Hancock International Dynamic Growth Fund
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	<span style="color:#000000;font-family:Arial Narrow;font-size:24pt;">John Hancock International Dynamic Growth Fund</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 capital appreciation.
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 you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	<span style="color:#000000;font-family:Arial Narrow;font-size:8pt;font-weight:bold;margin-left:0.0pt;">Shareholder fees (%) </span><span style="color:#000000;font-family:Arial Narrow;font-size:8pt;margin-left:0.0pt;">(fees paid directly from your investment)</span>
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;">February 28, 2026</span><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 and may result in higher taxes when fund shares are held in a taxable account. 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 83% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	83.00%
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	This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. Please see below a hypothetical example showing the expenses of a $10,000 investment for the time periods indicated and then assuming you sell all of your shares at the end of those periods. The example assumes a 5% average annual return and that fund expenses will not change over the periods. 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	The manager seeks to achieve the fund’s investment objective by investing in equity investments that the manager believes will provide higher returns than the MSCI ACWI ex USA Growth Index. The fund primarily invests in a diversified portfolio of equity securities of foreign companies in a number of developed and emerging markets. The fund defines foreign companies as companies: (i) that are organized under the laws of a foreign country; (ii) whose principal trading market is in a foreign country; or (iii) that have a majority of their assets, or that derive a majority of their revenue or profit growth, from businesses, investments or sales outside of the United States. The manager will consider, but is not limited to, MSCI market classifications in determining whether a country is a developed or emerging market country. Although the fund may invest in companies of any market-capitalization, the fund typically invests in companies with a market capitalization over $250 million. The fund may focus its investments in a particular sector or sectors of the economy. The fund invests primarily in common stocks, but may also invest in participatory notes. The manager’s growth philosophy and process is focused on fundamental, bottom-up stock selection and includes three key elements: (i) positive fundamental changes, (ii) sustainable earnings growth, and (iii) an attractive valuation. The manager’s investment process generally begins with the broad universe of securities included in international equity indices, including China A-shares. The manager then focuses its fundamental research by collecting, scoring and monitoring forward-looking operational data related to specific companies, industries, and sectors. It then seeks to identify quantifiable changes by consistently tracking these data points. Once the manager has identified a positive change, it holistically assesses the key company, industry, secular, macro and country stock drivers and compares them to consensus expectations. The manager then determines a risk/return rating for each company it has identified. This ranking is utilized by the portfolio management team to build a portfolio with consistent and balanced risk/return characteristics. The manager considers environmental, social, and/or governance (ESG) factors, alongside other relevant factors, as part of its investment process. ESG factors may include, but are not limited to, matters regarding board diversity, climate change policies, and supply chain and human rights policies. The ESG characteristics utilized in the fund’s investment process may change over time and one or more characteristics may not be relevant with respect to all issuers that are eligible fund investments. Because ESG factors are considered alongside other relevant factors, the manager may determine that an investment is appropriate notwithstanding its relative ESG characteristics. The operational metrics and investment thesis of the portfolio’s holdings are continuously monitored to ensure the ranking and weighting of each security in the portfolio is appropriate given the level of risk/return. The fund may trade securities actively as the investment thesis improves or deteriorates.
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 (before and after taxes) does not indicate future results. The MSCI ACWI ex USA Growth Index shows how the fund’s performance compares against the returns of similar investments. All figures assume dividend reinvestment. Performance information is updated daily, monthly, and quarterly and may be obtained by calling 800-344-1029 between 8:00 a.m. and 7:00 p.m., Eastern time, on most business days.Please note that after-tax returns reflect the highest individual federal marginal income-tax rate in effect as of the date provided and do not reflect any state or local taxes. Your actual after-tax returns may be different. After-tax returns are not relevant to shares held in an IRA, 401(k), or other tax-advantaged investment plan.
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 Availability Phone [Text]	rr_PerformanceAvailabilityPhone	<span style="font-family:Arial Narrow;font-size:9pt;">800-344-1029 between 8:00 </span><span style="font-family:Arial Narrow;font-size:9pt;font-variant:small-caps;">a.m.</span><span style="font-family:Arial Narrow;font-size:9pt;"> and 7:00</span><span style="font-family:Arial Narrow;font-size:9pt;line-height:12pt;"> </span><span style="font-family:Arial Narrow;font-size:9pt;font-variant:small-caps;">p.m.</span><span style="font-family:Arial Narrow;font-size:9pt;">, Eastern time, on most business days.</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="font-family:Arial Narrow;font-size:9pt;">Past performance (before and after taxes) 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 (%)—Class NAV</span>
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best quarter:Q2 202026.92%Worst quarter:Q2 2022-16.97%
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 MSCI ACWI ex USA Index as its new broad-based securities market index in accordance with the revised definition for such an index.</span>
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	<span style="color:#000000;font-family:Arial Narrow;font-size:9pt;">Please note that after-tax returns reflect the highest individual federal marginal income-tax rate in effect as of the date provided and do not reflect any state or local taxes.</span>
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	<span style="color:#000000;font-family:Arial Narrow;font-size:9pt;"> Your actual after-tax returns may be different. After-tax returns are not relevant to shares held in an IRA, 401(k), or other </span><span style="color:#000000;font-family:Arial Narrow;font-size:9pt;">tax-advantaged investment plan.</span>
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | Credit And Counterparty Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Credit and counterparty risk.  A borrower of fund securities may not make timely payments or otherwise honor its obligations.
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | 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. Growth company securities may fluctuate more in price than other securities because of the greater emphasis on earnings expectations. 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.
Class NAV | John Hancock International Dynamic Growth Fund | ESG Integration Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	ESG integration risk.  The manager considers ESG factors that it deems relevant or additive, along with other material factors and analysis, when managing the fund. ESG factors may include, but are not limited to, matters regarding board diversity, climate change policies, and supply chain and human rights policies. The manager may consider these ESG factors on all or a meaningful portion of the fund’s investments. Incorporating ESG criteria and making investment decisions based on certain ESG characteristics, as determined by the manager, carries the risk that the fund may perform differently, including underperforming, funds that do not utilize ESG criteria, or funds that utilize different ESG criteria.
Class NAV | John Hancock International Dynamic Growth Fund | 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. The risks of investing in foreign securities are magnified in emerging markets.
Class NAV | John Hancock International Dynamic Growth Fund | Hong Kong Stock Connect Program (Stock Connect) Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Hong Kong Stock Connect Program (Stock Connect) risk.  Trading in China A-Shares through Stock Connect, a mutual market access program that enables foreign investment in the People’s Republic of China (PRC), is subject to certain restrictions and risks. Securities listed on Stock Connect may lose purchase eligibility, which could adversely affect the fund’s performance. Trading through Stock Connect is subject to trading, clearance, and settlement procedures that may continue to develop as the program matures. Any changes in laws, regulations and policies applicable to Stock Connect may affect China A-Share prices. These risks are heightened by the underdeveloped state of the PRC’s investment and banking systems in general.
Class NAV | John Hancock International Dynamic Growth Fund | Geographic Focus Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Geographic focus risk.  The fund’s performance will be closely tied to the market, currency, economic, political, regulatory, geopolitical, and other conditions in the countries or regions in which the fund’s assets are invested and may be more volatile than the performance of more geographically-diversified funds.
Class NAV | John Hancock International Dynamic Growth Fund | High Portfolio Turnover Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	High portfolio turnover risk.  Trading securities actively and frequently can increase transaction costs (thus lowering performance) and taxable distributions.
Class NAV | John Hancock International Dynamic Growth Fund | Information Technology Companies Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Information technology companies risk.  Information technology companies can be significantly affected by rapid obsolescence, short product cycles, competition from new market entrants, and heightened cybersecurity risk, among other factors.
Class NAV | John Hancock International Dynamic Growth Fund | Large Company Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Large company risk.  Larger companies may grow more slowly than smaller companies or be slower to respond to business developments. Large-capitalization securities may underperform the market as a whole.
Class NAV | John Hancock International Dynamic Growth Fund | 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 without negatively impacting its market value may be impaired by reduced market activity or participation, legal restrictions, or other economic and market impediments.
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | Participatory Notes Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Participatory notes risk.  Participatory notes (p-notes) represent interests in securities listed on certain foreign exchanges. Due to transaction costs and other expenses, p-notes will not replicate exactly the performance of their underlying securities. P-notes are general unsecured contractual obligations of the financial institutions issuing the notes and are subject to liquidity risk and a high degree of counterparty risk.
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | 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.
Class NAV | John Hancock International Dynamic Growth Fund | Class NAV
Risk Return Abstract	rr_RiskReturnAbstract
Maximum front-end sales charge (load)	rr_MaximumCumulativeSalesChargeOverOther	none
Maximum deferred sales charge (load)	rr_MaximumDeferredSalesChargeOverOther	none
Management fee	rr_ManagementFeesOverAssets	0.80%
Other expenses	rr_OtherExpensesOverAssets	0.09%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.89%
Contractual expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.06%)	[1]
Total annual fund operating expenses after expense reimbursements	rr_NetExpensesOverAssets	0.83%
1 year	rr_ExpenseExampleYear01	$ 85
3 years	rr_ExpenseExampleYear03	278
5 years	rr_ExpenseExampleYear05	487
10 years	rr_ExpenseExampleYear10	$ 1,091
2020	rr_AnnualReturn2020	36.75%
2021	rr_AnnualReturn2021	18.67%
2022	rr_AnnualReturn2022	(31.44%)
2023	rr_AnnualReturn2023	19.01%
2024	rr_AnnualReturn2024	25.16%
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	Jun. 30, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	26.92%
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	Jun. 30, 2022
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(16.97%)
1 year	rr_AverageAnnualReturnYear01	25.16%
5 year	rr_AverageAnnualReturnYear05	10.63%
Since inception	rr_AverageAnnualReturnSinceInception	11.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 17, 2019
Class NAV | John Hancock International Dynamic Growth Fund | Return After Taxes on Distributions | Class NAV
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	25.04%
5 year	rr_AverageAnnualReturnYear05	8.69%
Since inception	rr_AverageAnnualReturnSinceInception	9.83%
Class NAV | John Hancock International Dynamic Growth Fund | Return After Taxes on Distributions and Sale of Shares | Class NAV
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	14.89%
5 year	rr_AverageAnnualReturnYear05	8.04%
Since inception	rr_AverageAnnualReturnSinceInception	8.91%
Class NAV | John Hancock International Dynamic Growth Fund | MSCI ACWI ex USA Index (reflects no deduction for fees, expenses, or taxes, except foreign withholding taxes on dividends)
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	5.53%	[2]
5 year	rr_AverageAnnualReturnYear05	4.10%	[2]
Since inception	rr_AverageAnnualReturnSinceInception	4.81%	[2]
Class NAV | John Hancock International Dynamic Growth Fund | MSCI ACWI ex USA Growth Index (reflects no deduction for fees, expenses, or taxes, except foreign withholding taxes on dividends)
Risk Return Abstract	rr_RiskReturnAbstract
1 year	rr_AverageAnnualReturnYear01	5.07%
5 year	rr_AverageAnnualReturnYear05	3.44%
Since inception	rr_AverageAnnualReturnSinceInception	4.78%

[1] The advisor contractually agrees to reduce its management fee or, if necessary, make payment to the fund in an amount equal to the amount by which expenses of the fund exceed 0.83% of average daily net assets of the fund. For purposes of this agreement, “expenses of the fund” means all fund expenses, excluding (a) taxes, (b) brokerage commissions, (c) interest expense, (d) litigation and indemnification expenses and other extraordinary expenses not incurred in the ordinary course of the fund’s business, (e) class-specific expenses, (f) borrowing costs, (g) prime brokerage fees, (h) acquired fund fees and expenses paid indirectly, and (i) short dividend expense. This agreement expires on February 28, 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. The advisor also 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 MSCI ACWI ex USA Index as its new broad-based securities market index in accordance with the revised definition for such an index.