Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Net income	$ 249,897	$ 251,057	$ 422,273
Other comprehensive (loss) income
Unrealized gain (loss) on foreign currency translation	75,339	(171,652)	(84,470)
Realized and unrealized (loss) gain on derivative financial instruments	(75,907)	173,366	81,608
Other comprehensive (loss) income	(568)	1,714	(2,862)
Comprehensive income	249,329	252,771	419,411
Comprehensive income attributable to non-controlling interests	(3,342)	(2,415)	(3,080)
Comprehensive income attributable to Blackstone Mortgage Trust, Inc.	$ 245,987	$ 250,356	$ 416,331