Accrued and other liabilities: (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accrued and other liabilities:
Operating accruals	$ 16,360	$ 24,168
Deferred revenue - current portion	4,894	4,651
Payroll and benefits	8,466	8,024
Taxes-non-income based	4,291	5,918
Interest	5,046	8,268
Total	$ 39,057	$ 51,029

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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