State Street SPDR Portfolio SP 400 Mid Cap ETF Expense Example - State Street SPDR Portfolio SP 400 Mid Cap ETF - State Street SPDR Portfolio SP 400 Mid Cap ETF	Jun. 30, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 3
Expense Example, with Redemption, 3 Years	10
Expense Example, with Redemption, 5 Years	17
Expense Example, with Redemption, 10 Years	$ 39

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