Real Estate - Summary of Consideration Transferred (Details) - Mergers $ / shares in Units, $ in Thousands	Mar. 01, 2021 USD ($) $ / shares shares
Real Estate [Line Items]
CCIT II's common stock shares prior to conversion	67,139,129
Exchange ratio	1.392
Implied GRT common stock issued as consideration	93,457,668
GRT's Class E NAV per share in effect at March 1, 2021 | $ / shares	$ 8.97
Total consideration | $	$ 838,315