Accounts Payable and Accrued Liabilities (Schedule of Accounts Payable and Accrued Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts Payable and Accrued Liabilities [Abstract]
Accounts payable	$ 16,115	$ 11,939
Accrued property taxes	2,835	2,763
Accrued payroll	2,151	1,825
Workers' compensation reserve	3,446	3,670
Group health insurance	2,500	2,200
Other	4,753	4,024
Total accounts payable and accrued liabilities	$ 31,800	$ 26,421