SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Summary of Developments by Category) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Land and improvements	$ 407,926	$ 423,520
Development costs	744,748	1,022,477
Total Developments	$ 1,152,674	$ 1,445,997