CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)	12 Months Ended
	Dec. 31, 2019 USD ($) tenant $ / shares $ / item shares	Dec. 31, 2018 USD ($) $ / item	Dec. 31, 2017 USD ($)
Supplemental Disclosure of Cash Flows:
Interest paid	$ 10,782,000	$ 8,419,000	$ 7,060,000
Income taxes paid	2,500,000	323,000	334,000
Income taxes refunded	687,000	204,000	958,000
Interest capitalized	0	0	215,000
Gain on Sale	133,000,000		31,800,000
Stock Issuance	531,914	238,712	103,136
Accrued and Other Liabilities	489,308	(4,357,411)	792,629
Land and Development Costs	(1,107,446)	5,477,221	12,477,581
Supplemental disclosure of investing and financing activities
Tenant contribution		$ 1,900,000
Purchase price	$ 164,670,000
Annual surcharge, per round of golf played | $ / item	1	1
Annual Minimum Per Round Surcharge	$ 70,000
Maximum aggregate amount of per round surcharge	700,000	$ 700,000
Contingent consideration on Golf Course Land Purchase reflected as an increase in increase in Golf Buildings, Improvements, and Equipment and also as an increase in Accrued and Other Liabilities	700,000
Repayment in connection with Gulf course sale	560,000
Remaining liability for Gulf course sale	0
Net cash provided by Operating activities discontinued operations	6,500,000	36,800,000	43,300,000
Net cash provided by investing activities discontinued operations	98,400,000	0	$ 0
Aspen, Colorado
Supplemental disclosure of investing and financing activities
Tenant contribution	1,500,000	1,500,000
Purchase price		$ 28,000,000
Florida
Supplemental disclosure of investing and financing activities
Tenant contribution	1,900,000
Alpine
Supplemental Disclosure of Cash Flows:
Increase in the Investment in Joint Ventures	23,300,000
Decrease in intangible assets	3,100,000
Decrease in Property Plant and Equipment	20,800,000
Decrease in intangible liabilities	$ 452,000
OP Units
Supplemental Disclosure of Cash Flows:
Number of single tenant properties | tenant	5
OP Units | Alpine
Supplemental Disclosure of Cash Flows:
Units issued | shares	1,223,854
Stock Issuance	$ 23,300,000
Closing share price (in dollars per share) | $ / shares	$ 19.00
Land Sales | Land JV
Supplemental Disclosure of Cash Flows:
Gain on Sale	$ 127,500,000
Gain on Sale, noncash	48,900,000
Increase in the Investment in Joint Ventures	48,900,000
Land Sales | Mitigation Bank West of Interstate Ninety Five
Supplemental Disclosure of Cash Flows:
Gain on Sale	18,400,000
Gain on Sale, noncash	5,100,000
Increase in the Investment in Joint Ventures	6,800,000
Accrued and Other Liabilities	300,000
Land and Development Costs	$ 1,300,000