John Hancock Global Climate Action Fund Expense Example - Class NAV [Member] - John Hancock Global Climate Action Fund - Class NAV	Mar. 31, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 86
Expense Example, with Redemption, 3 Years	582
Expense Example, with Redemption, 5 Years	1,105
Expense Example, with Redemption, 10 Years	$ 2,541

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