Investment in Unconsolidated and Consolidated Joint Ventures - Investment Information (Details)		1 Months Ended		3 Months Ended				12 Months Ended
	Apr. 01, 2019 USD ($)	Nov. 30, 2019 USD ($)	Nov. 30, 2018 ft²	Mar. 31, 2020 USD ($) a ft² joint_venture	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2013 USD ($) member	Dec. 31, 2019 USD ($) a	Dec. 31, 2013 ft²	Jun. 01, 2018 USD ($)
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated joint ventures				$ 39,554,000	$ 38,240,000			$ 38,240,000
Equity in earnings (loss)				1,355,000		$ 876,000
Equity				39,554,000	38,240,000			38,240,000
Debt				$ 133,847,000	131,254,000			131,254,000
Centennial
Schedule of Equity Method Investments [Line Items]
Consolidated joint venture, ownership interest				92.63%
Petro Travel Plaza Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Unconsolidated joint ventures, ownership interest				50.00%
Right and share of profit and loss				60.00%
Equity				$ 25,159,000	23,636,000			23,636,000
Debt				15,288,000	15,287,000			15,287,000
Majestic Realty Co.
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated joint ventures				$ 24,773,000
Number of joint venture contracts | joint_venture				3
Area of building owned and leased | ft²				651,909
TRC-MRC 3, LLC
Schedule of Equity Method Investments [Line Items]
Equity				$ 6,016,000	$ 5,953,000			5,953,000
Number of acres for development | ft²			579,040
Lease agreement, rentable space					67.00%
Debt				31,375,000	$ 28,061,000			28,061,000
TRC-MRC 3, LLC | Land
Schedule of Equity Method Investments [Line Items]
Value of property contributed	$ 5,854,000
TRC-MRC 2, LLC
Schedule of Equity Method Investments [Line Items]
Equity				0	0			0
Debt				24,311,000	24,455,000			24,455,000
Debt instrument face amount										$ 25,240,000
Deficit balance				$ 2,374,000
TRCC-East
Schedule of Equity Method Investments [Line Items]
Number of acres for development | ft²									326,000
Area of building owned and leased | ft²				480,480
Deficit balance				$ 488,000
TRC-MRC 1, LLC
Schedule of Equity Method Investments [Line Items]
Equity				0	0			0
Debt				24,405,000	24,542,000			24,542,000
Construction Loan				$ 25,030,000
Rockefeller Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of joint venture contracts | joint_venture				3
Number of acres for development | a				91
Investment in unconsolidated joint ventures				$ 8,379,000
Development of land in TRCC including pursuing foreign trade zone (up to) | a				500
Rockefeller Joint Ventures | Building Development
Schedule of Equity Method Investments [Line Items]
Number of joint venture contracts | joint_venture				2
Five West Parcel, LLC
Schedule of Equity Method Investments [Line Items]
Unconsolidated joint ventures, ownership interest				50.00%					50.00%
Equity				$ 139,000	140,000			140,000
Debt				$ 0	0			0
Area of building owned and leased | ft²				606,000
Purchase price		$ 29,088,000
Gain realized on sale		$ 17,537,000
18-19 West, LLC
Schedule of Equity Method Investments [Line Items]
Equity				$ 1,615,000	1,730,000			1,730,000
Debt				0	0			$ 0
Number of acres for development | a								61.5
TRCC/Rock Outlet Center, LLC
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated joint ventures							$ 87,000,000
Equity				6,625,000	6,781,000			$ 6,781,000
Debt				$ 38,468,000	$ 38,909,000			$ 38,909,000
Construction loan percent of costs							60.00%
Equity contributions							40.00%
Number of members | member							2