COMMON STOCK AND EARNINGS PER SHARE (Details)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Jul. 12, 2021
property
shares
Jun. 30, 2021
property
shares
Sep. 30, 2021
USD ($)
property
$ / shares
shares
Sep. 30, 2020
USD ($)
$ / shares
shares
Sep. 30, 2021
USD ($)
property
$ / shares
shares
Sep. 30, 2020
USD ($)
$ / shares
shares
Income Available to Common Shareholders:            
Net Income Attributable to Alpine Income Property Trust, Inc. | $     $ 918 $ 546 $ 1,662 $ 799
Net Income Attributable to Alpine Income Property Trust, Inc. - Basic | $     918 546 1,662 799
Net Income Attributable to Alpine Income Property Trust, Inc. - Diluted | $     $ 918 $ 546 $ 1,662 $ 799
Weighted Average Number of Common Shares Outstanding (in shares)     11,299,548 7,455,281 9,253,090 7,632,660
Common Shares Applicable to Stock            
Weighted Average Number of Common Shares Applicable to OP Units using Treasury Stock Method (in shares)     1,696,955 1,223,854 1,384,844 1,223,854
Total Shares Applicable to Diluted Earnings Per Share (in shares)     12,996,503 8,679,135 10,637,934 8,856,514
Net Income Attributable to Alpine Income Property Trust, Inc.            
Basic (in dollars per share) | $ / shares     $ 0.08 $ 0.07 $ 0.18 $ 0.10
Diluted (in dollars per share) | $ / shares     $ 0.07 $ 0.06 $ 0.16 $ 0.09
Partners' capital account, units issued 54,689 424,951     479,640  
Number of lease properties acquired | property 1 9 10   10  
CTO            
Net Income Attributable to Alpine Income Property Trust, Inc.            
Partners' capital account, units issued         1,223,854