Expense Example - BRUCE FUND - BRUCE FUND	Oct. 26, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 58
Expense Example, with Redemption, 3 Years	183
Expense Example, with Redemption, 5 Years	318
Expense Example, with Redemption, 10 Years	$ 714

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