Name:	stwd_AmountOfNetGainOrLossFromSaleOfFinancialAssetsInSecuritizations
Namespace Prefix:	stwd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	stwd_LoanTransferActivitiesLineItems
Namespace Prefix:	stwd_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	stwd_LoanTransfersAccountedForAsSalesAbstract
Namespace Prefix:	stwd_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Represents the fair value of loans held-for-sale, sold during the period.

No definition available.

Name:	stwd_LoansHeldForSaleSoldFairValue
Namespace Prefix:	stwd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the par value of loans held-for-sale, sold during the period.

No definition available.

Name:	stwd_LoansHeldForSaleSoldParValue
Namespace Prefix:	stwd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Face amount of assets transferred during the period related to either a securitization, asset-backed financing arrangement, or similar transfer accounted for as a sale.

No definition available.

Name:	stwd_SecuritizationFinancialAssetForWhichTransferIsAccountedAsSaleFaceAmount
Namespace Prefix:	stwd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorProceedsFromNewTransfers
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

Name:	us-gaap_RepaymentsOfSecuredDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Name:	us-gaap_StatementBusinessSegmentsAxis=stwd_LNRBusinessSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_StatementBusinessSegmentsAxis=stwd_CommercialAndResidentialLendingSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stwd_LoansHeldForSaleCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stwd_LoansHeldForSaleResidentialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: