Label

Element

Value

Prospectus Line Items

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Document Type

dei_DocumentType

497

Document Period End Date

dei_DocumentPeriodEndDate

Oct. 31, 2019

Entity Registrant Name

dei_EntityRegistrantName

JOHN HANCOCK INVESTMENT TRUST

Entity Central Index Key

dei_EntityCentralIndexKey

0000022370

Amendment Flag

dei_AmendmentFlag

false

Entity Inv Company Type

dei_EntityInvCompanyType

N-1A

Document Creation Date

dei_DocumentCreationDate

Sep. 17, 2020

Document Effective Date

dei_DocumentEffectiveDate

Sep. 17, 2020

John Hancock Infrastructure Fund

Prospectus Line Items

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Strategy Narrative [Text Block]

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The fund pursues its objective by investing, under normal circumstances, at least 80% of its net assets (plus borrowings for investment purposes) in global securities of companies with infrastructure-related assets. Because the fund normally invests

more than 25% of its assets in global securities of infrastructure-related assets, the fund is considered to be “concentrated” in industries represented by infrastructure companies. For purposes of this policy, global securities include: common stock, depositary receipts, real estate securities (including real estate investment trusts (REITs)), master limited partnerships (MLPs) (up to a maximum of 25% of the fund’s net assets), preferred stock, rights, warrants, exchange-traded funds (ETFs), and debt securities (up to a maximum of 20% of the fund’s net assets). Also for purposes of this policy, infrastructure-related assets are long-lived physical assets that are held by companies, including financial holding companies, that engage in the ownership, management, construction, development, renovation, operation, use or financing of infrastructure assets, or that provide the services and raw materials necessary for the construction and maintenance of infrastructure assets. Infrastructure assets are the physical structures, networks and systems which provide necessary services for the function, growth and development of society, including but not limited to utilities, pipelines, toll roads, airports, railroads, ports, telecommunications and other infrastructure companies.