CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
General and administrative expense	$ 13,457,000	$ 8,969,000	$ 24,912,000	$ 18,071,000
Rental income	246,000	0	492,000	0
Interest income (expense)	(1,128,000)	(705,000)	(850,000)	(4,011,000)
VIE, Primary Beneficiary
General and administrative expense	700,000	500,000	1,300,000	600,000
Rental income	200,000	0.0	500,000	0.0
Interest income (expense)	$ 800,000	$ 100,000	$ 0.0	$ 2,600,000