v3.26.3
Cover
Oct. 05, 2026
Document Information [Line Items]  
Document Type 8-K
Amendment Flag false
Document Period End Date Oct. 05, 2026
Current Fiscal Year End Date --12-31
Entity File Number 001-38124
Entity Registrant Name Granite Point Mortgage Trust Inc.
Entity Central Index Key 0001703644
Entity Tax Identification Number 61-1843143
Entity Incorporation, State or Country Code MD
Entity Address, Address Line One 1114 Avenue of the Americas
Entity Address, Address Line Two Suite 3020
Entity Address, City or Town New York
Entity Address, State or Province NY
Entity Address, Postal Zip Code 10036
City Area Code 212
Local Phone Number 364-5500
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Common Stock [Member]  
Document Information [Line Items]  
Title of 12(b) Security Common Stock, par value $0.01 per share
Trading Symbol GPMT
Security Exchange Name NYSE
Series A 700percentage Fixedto Floating Rate Cumulative Redeemable Preferred Stockparvaluedollar 001pershare [Member]  
Document Information [Line Items]  
Title of 12(b) Security 7.00% Series A Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock, par value $0.01 per share
Trading Symbol GPMTPrA
Security Exchange Name NYSE