Mid Cap Growth Stock Portfolio Expense Example - Mid Cap Growth Stock Portfolio - Mid Cap Growth Stock Portfolio	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 55
Expense Example, with Redemption, 3 Years	173
Expense Example, with Redemption, 5 Years	302
Expense Example, with Redemption, 10 Years	$ 677

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