Equity - Carrying Amounts and Classification of Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 68,899	$ 71,684
Accounts receivable	66,676	70,350
Other current assets	14,129	11,818
Total current assets	196,680	204,874
Goodwill	120,343	120,343	$ 120,343	$ 120,343
Other assets	3,624	4,139
Total Assets	355,276	366,667	$ 422,968
Current liabilities:
Accounts Payable and Accrued Liabilities	43,285	27,322
Other current liabilities	1,707	1,295
Total current liabilities	82,492	90,661
Long-term liabilities:
Long-term portion of Senior Credit Facility	135,000	100,000
Other long-term liabilities	109	30
Total liabilities	217,637	190,918
Variable Interest Entity, Primary Beneficiary
Current assets:
Cash and cash equivalents	68,703	71,442
Accounts receivable	66,676	70,350
Other current assets	56,392	55,575
Total current assets	191,771	197,367
Goodwill	120,343	120,343
Other assets	16,758	15,259
Total non-current assets	137,101	135,602
Total Assets	328,872	332,969
Current liabilities:
Accounts Payable and Accrued Liabilities	62,538	61,436
Other current liabilities	49,328	43,676
Total current liabilities	111,866	105,112
Long-term liabilities:
Long-term portion of Senior Credit Facility	135,000	100,000
Other long-term liabilities	145	256
Liabilities, Noncurrent, Total	135,145	100,256
Total liabilities	$ 247,011	$ 205,368