S000000002 [Member] Expense Example - SA Franklin Mid Cap Core Portfolio - Class 3	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 98
Expense Example, with Redemption, 3 Years	316
Expense Example, with Redemption, 5 Years	561
Expense Example, with Redemption, 10 Years	$ 1,266

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