Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts payable and other accrued liabilities:
Accounts payable	$ 33,421	$ 20,177
Accrued liabilities	14,249	15,356
Total Accounts payable and other accrued liabilities	47,670	35,533
Accrued payroll costs:
Payroll and benefits	49,986	38,257
Payroll taxes	26,704	21,842
Health insurance liabilities	4,736	4,641
Workers’ compensation liabilities	1,060	1,109
Total Accrued payroll costs	$ 82,486	$ 65,849