Stock Index Fund Expense Example - Stock Index Fund - Stock Index Fund	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 45
Expense Example, with Redemption, 3 Years	141
Expense Example, with Redemption, 5 Years	246
Expense Example, with Redemption, 10 Years	$ 555

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