Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income from loans and other investments
Interest and related income	$ 184,766	$ 53,164	$ 34,939
Less: Interest and related expenses	69,143	18,017	38,138
Income (loss) from loans and other investments, net	115,623	35,147	(3,199)
Other expenses
Management and incentive fees	19,491	5,937
General and administrative expenses	27,799	11,505	10,369
Total other expenses	47,290	17,442	10,369
Recovery of provision for loan losses			36,147
Valuation allowance on loans held-for-sale	1,300	1,259
Unrealized gain on investments at fair value	13,258	7,417	51,904
(Loss) gain on deconsolidation of subsidiary	(8,615)		200,283
Other income		38	5,840
Income from equity investments in unconsolidated subsidiaries	28,036		1,781
Income before income taxes	101,012	26,419	282,387
Income tax provision	518	995	174
Income from continuing operations	100,494	25,424	282,213
Loss from discontinued operations, net of tax			(2,138)
Loss on sale of discontinued operations			(271)
Net income	100,494	25,424	279,804
Net income attributable to non-controlling interests	(10,449)	(10,392)	(98,780)
Net income attributable to Blackstone Mortgage Trust, Inc.	$ 90,045	$ 15,032	$ 181,024
Income from continuing operations per share of common stock
Basic	$ 1.86	$ 0.81	$ 78.19
Diluted	$ 1.86	$ 0.81	$ 74.16
Loss from discontinued operations per share of common stock
Basic			$ (1.03)
Diluted			$ (1.03)
Net income per share of common stock
Basic	$ 1.86	$ 0.81	$ 77.16
Diluted	$ 1.86	$ 0.81	$ 73.13
Weighted-average shares of common stock outstanding
Basic	48,394,478	18,520,052	2,345,943
Diluted	48,394,478	18,520,052	2,475,294