CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
General and administrative expense	$ 11,455,000	$ 9,102,000
Rental income	246,000	0
Interest income (expense)	278,000	(3,306,000)
VIE, Primary Beneficiary
General and administrative expense	600,000	100,000
Rental income	200,000	0
Interest income (expense)	$ 800,000	$ 2,400,000