Real Estate Index Portfolio Annual Fund Operating Expenses - Portfolio [Member] - Real Estate Index Portfolio - Real Estate Index Portfolio	Dec. 31, 2025
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.24%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses (as a percentage of Assets):	0.02%
Expenses (as a percentage of Assets)	0.26%

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