Supplemental Disclosure of Statement of Cash Flow Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Significant Noncash Transactions [Line Items]
Cash and cash equivalents	$ 178,795,000	$ 122,666,000	$ 168,750,000	$ 107,762,000
Restricted cash	626,000	6,644,000	8,497,000	4,394,000
Cash, cash equivalents, and restricted cash	179,421,000	129,310,000	177,247,000	$ 112,156,000
Interest paid	52,059,000	59,018,000	76,562,000
Income taxes paid, net	1,748,000	1,482,000	$ 2,025,000
Non-Recourse Mortgage
Other Significant Noncash Transactions [Line Items]
Face amount	178,662,000	110,000,000
Mortgage debt incurred upon the acquisition of property		$ 41,877,000
South Carolina, Kansas and Florida
Other Significant Noncash Transactions [Line Items]
Transfer mortgage payable	57,356,000
Real estate, net	28,078,000
Owensboro Kentucky and Orlando Florida
Other Significant Noncash Transactions [Line Items]
Lease obligation incurred	719,000
Right-of-use asset obtained	$ 719,000