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Assetsfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalsefalse00falsefalsefalsefalsefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7truefalsefalse150770000000150770falsetruefalsetruefalse8truefalsefalse140978000000140978falsetruefalsetruefalse9truefalsefalse138914000000138914falsetruefalse truefalse10truefalsefalse147908000000147908falsetruefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAdjusted Total Risk Weighted Assets And Market Risk Equivalents Adjusted Quarterly Average AssetsNo authoritative reference available.falsefalse1 State Street Bank must meet the regulatory designation of "well capitalized" in order for us to maintain our status as a financial holding company, including maintaining a minimum tier 1 risk-based capital ratio (tier 1 capital divided by adjusted total risk-weighted assets and market-risk equivalents) of 6%, a minimum total risk-based capital ratio (total capital divided by adjusted total risk-weighted assets and market-risk equivalents) of 10%, and a tier 1 leverage ratio (tier 1 capital divided by adjusted quarterly average assets) of 5%. The "well capitalized" designation requires us to maintain a minimum tier 1 risk-based capital ratio of 6% and a minimum total risk-based capital ratio of 10%. 2 Amounts include deferred tax assets not eligible for inclusion in capital. 1023Regulatory Matters (Regulatory Capital Ratios And Related Amount) (Details) (USD $)MillionsUnKnownUnKnownUnKnowntruetrue