Industry Segment and Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	$ 135,748	$ 128,738	$ 122,869	$ 117,842	$ 112,329	$ 113,587	$ 91,119	$ 108,508	$ 505,198	$ 425,544	$ 424,625
Long-lived assets	78,050				82,705				78,050	82,705
Total assets	530,818				471,217				530,818	471,217
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									432,188	376,426	369,163
Long-lived assets	46,092				48,805				46,092	48,805
Total assets	391,328				365,748				391,328	365,748
Asia
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									16,736	6,437	9,111
Canada
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									11,867	10,406	13,568
Europe
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									30,359	18,255	15,784
Long-lived assets	13,991				15,142				13,991	15,142
Total assets	118,359				83,174				118,359	83,174
Mexico
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									5,110	4,886	5,791
Long-lived assets	17,967				18,758				17,967	18,758
Total assets	$ 21,131				$ 22,295				21,131	22,295
Middle East
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									7,176	6,114	7,868
Other
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									$ 1,762	$ 3,020	$ 3,340