Goodwill and Intangibles - Future Expected Amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Asset Amortization
2026 (remainder of)	$ 14,069
2027	27,978
2028	27,975
2029	27,941
2030	27,688
Thereafter	285,836
Total	411,487
Liability Amortization
2026 (remainder of)	(1,214)
2027	(2,424)
2028	(2,423)
2029	(2,422)
2030	(2,422)
Thereafter	(22,143)
Net Carrying Value	$ (33,048)	$ (32,682)

Finite-Lived Intangible Asset, Expected Amortization, after Year Four

No definition available.

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Period Type:	instant

- Definition

Off-Market Lease, Unfavorable, Expected Amortization, after Year Four

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Off-Market Lease, Unfavorable, Expected Amortization, Remainder of Fiscal Year

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Off-Market Lease, Unfavorable, Expected Amortization, Year Four

+ References

No definition available.

+ Details

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Namespace Prefix:	stwd_
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Period Type:	instant

- Definition

Off-Market Lease, Unfavorable, Expected Amortization, Year One

+ References

No definition available.

+ Details

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- Definition

Off-Market Lease, Unfavorable, Expected Amortization, Year Three

+ References

No definition available.

+ Details

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- Definition

Off-Market Lease, Unfavorable, Expected Amortization, Year Two

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Off-Market Lease, Unfavorable, Net, Amortization Expense, Fiscal Year Maturity

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of amortization expense for finite-lived intangible asset expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 40
-SubTopic 30
-Topic 350
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482640/350-30-55-40

+ Details

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- Definition

Amount of amortization expense for finite-lived intangible asset expected to be recognized in remainder of current fiscal year. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

+ Details

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- Definition

Amount of amortization expense for finite-lived intangible asset expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

+ Details

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- Definition

Amount of amortization expense for finite-lived intangible asset expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of amortization expense for finite-lived intangible asset expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483154/926-20-50-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a liability associated with the acquisition of an off-market lease when the terms of the lease are unfavorable to the market terms for the lease at the date of acquisition.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant