Related Party Transactions - Summary of Management Fees and Incentive Management Fees Incurred and Paid Pursuant to Management Agreement (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Related Party Transactions [Abstract]
Management Agreement fees incurred	$ 6,508	$ 5,630
Management Agreement fees paid	$ 6,100	$ 5,232

Management fees and incentive management fees incurred.

No definition available.

Name:	trtx_ManagementFeesAndIncentiveManagementFeesIncurred
Namespace Prefix:	trtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration