Annual report pursuant to Section 13 and 15(d)

Schedule of Related Party Transactions, by Related Party (Details)

v3.8.0.1
Schedule of Related Party Transactions, by Related Party (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Related Party Transaction [Line Items]      
Management fees $ 40,472 $ 39,261 $ 49,116
Percent per annum of equity used to calculate management fees 1.50%    
Equity securities, at fair value $ 29,413 0  
PRCM Advisers LLC [Member]      
Related Party Transaction [Line Items]      
Management fees $ 40,472 39,262 49,117
Percent per annum of equity used to calculate management fees 1.50%    
Direct and allocated costs incurred by manager $ 18,983 18,597 16,746
Compensation costs related to restricted common stock $ 11,328 $ 15,198 $ 9,002
Granite Point Mortgage Trust Inc. [Member]      
Related Party Transaction [Line Items]      
Purchases of equity securities of related party (in shares) 1,658,008    
Purchases of equity securities of related party $ 30,049    
Equity securities, at fair value 29,413    
Equity securities, unrealized gain (loss) $ (641)