Name:	stt_OtherComprehensiveIncomeLossChangeInNetUnrealizedGainLossOnAfsSecuritiesNetOfReclassAndExpectedLossFromOttiRelatedTaxes
Namespace Prefix:	stt_
Data Type:	xbrli:monetaryItemType
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Other Comprehensive Income (Loss), Change in Unrealized Gain Loss on AFS Securities Designated as Fair Value Hedges, Related Taxes

No definition available.

Name:	stt_OtherComprehensiveIncomeLossChangeInUnrealizedGainLossOnAfsSecuritiesDesignatedAsFairValueHedgesRelatedTaxes
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Data Type:	xbrli:monetaryItemType
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Other Comprehensive Income (Loss), Expected Losses From OTTI on HTM Securities Not From Credit, Related Taxes

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Other Comprehensive Income (Loss), Minimum Pension Liability Net Adjustment, Tax

No definition available.

Name:	stt_OtherComprehensiveIncomeLossMinimumPensionLiabilityNetAdjustmentTax
Namespace Prefix:	stt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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- References

No definition available.