Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2021
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		286,985,112
Entity Central Index Key	0001465128
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false