Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 18, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-34436
Entity Registrant Name	Starwood Property Trust, Inc.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	27-0247747
Entity Address, Address Line One	591 West Putnam Avenue
Entity Address, City or Town	Greenwich
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06830
City Area Code	203
Local Phone Number	422-7700
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	STWD
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 7,164,419,530
Entity Common Stock, Shares Outstanding		304,827,055
Documents Incorporated by Reference	Documents Incorporated By Reference: The information required by Part III of this Form 10-K, to the extent not set forth herein or by amendment, is incorporated by reference from the registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission pursuant to Regulation 14A on or prior to May 2, 2022.
Entity Central Index Key	0001465128
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false