Expense Example - SIIT Screened World Equity Ex-US Fund - SIIT Screened World Equity Ex-US Fund - Class A	Oct. 03, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 84
Expense Example, with Redemption, 3 Years	262
Expense Example, with Redemption, 5 Years	455
Expense Example, with Redemption, 10 Years	$ 1,014

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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