XML 41 R29.htm IDEA: XBRL DOCUMENT v3.21.2
Identifiable net assets (Details) - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Segment Reporting Information [Line Items]    
Assets $ 681,252 $ 536,360
Investments available for sale 32,129 75,609
Cash 138,838 74,105
Asset Management [Member]    
Segment Reporting Information [Line Items]    
Assets 10,939 11,172
Mining Properties [Member]    
Segment Reporting Information [Line Items]    
Assets 37,338 37,387
Development [Member]    
Segment Reporting Information [Line Items]    
Assets 180,264 196,212
Stabilized Joint Venture [Member]    
Segment Reporting Information [Line Items]    
Assets 270,459 130,472
Unallocated Corporate Assets [Member]    
Segment Reporting Information [Line Items]    
Assets $ 11,285 $ 11,403