Schedule I - Condensed Financial Information of the Parent (Condensed Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 86,005	$ 88,450
Accounts receivable from affiliates	5,605	4,764
Other current assets	14,621	8,308
Other non-current assets	51,225	40,984
Total assets	507,220	476,179
LIABILITIES AND EQUITY
Current liabilities	46,016	52,257
Other long-term liabilities	7,531	12,060
Stockholders’ equity	352,116	300,624	$ 289,392
Total liabilities and equity	507,220	476,179
Parent Company
ASSETS
Cash and cash equivalents	83,093	85,365
Accounts receivable from affiliates	0	495
Other current assets	17,578	20,648
Investment in subsidiaries	268,720	211,468
Property, plant and equipment, net	57	110
Other non-current assets	4,885	5,890
Total assets	374,333	323,976
LIABILITIES AND EQUITY
Current liabilities	3,865	3,242
Current intercompany accounts payable, net	637	2,337
Other long-term liabilities	965	1,023
Stockholders’ equity	352,116	300,624
Total liabilities and equity	374,333	323,976
Parent Company | Bellaire
LIABILITIES AND EQUITY
Note payable to Bellaire	$ 16,750	$ 16,750