Property and Equipment (Details) - USD ($)	1 Months Ended	3 Months Ended				12 Months Ended
	Jan. 31, 2019	Mar. 31, 2020	Sep. 30, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property and equipment
Gross						$ 117,347,000	$ 111,179,000
Less accumulated depreciation						(67,272,000)	(63,042,000)
Net						50,075,000	48,137,000
Proceeds from sale of land						7,224,000	4,945,000
Gain (loss) on sale of land						4,325,000	2,413,000
Fair value of land							531,000
Capitalized costs charged to depreciation				$ 186,000
Depreciation						4,353,000	3,285,000	$ 3,566,000
Accelerated depreciation expense						1,172,000
Costs to remove long-lived assets					$ 286,000	1,170,000		$ 286,000
Total project cost paid						731,000
Parcel of land near St. Louis | Assets held for sale
Property and equipment
Proceeds from sale of land	$ 531,000
Gain (loss) on sale of land			$ (99,000)				(99,000)
Fair value of land							531,000
Forecast
Property and equipment
Costs to remove long-lived assets		$ 300,000
Land
Property and equipment
Gross						15,286,000	15,286,000
Facilities
Property and equipment
Gross						92,811,000	86,725,000
Furniture, fixtures and equipment
Property and equipment
Gross						9,087,000	8,893,000
Construction in progress
Property and equipment
Gross						$ 163,000	$ 275,000