Revenue Recognition - Revenues From Contracts With Customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenues	$ 73,182	$ 84,229	$ 219,829	$ 254,484
Western Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	50,484	47,069	146,600	149,458
Eastern Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	12,675	17,066	33,253	57,392
Asia Pacific | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	10,023	20,094
Asia Pacific Segment | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues			39,976	47,634
Products
Disaggregation Of Revenue [Line Items]
Revenues	53,622	66,451	165,066	197,142
Products | Western Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	37,612	36,095	112,787	114,364
Products | Eastern Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	10,217	13,377	25,505	45,772
Products | Asia Pacific | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	5,793	16,979
Products | Asia Pacific Segment | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues			26,774	37,006
Services
Disaggregation Of Revenue [Line Items]
Revenues	19,560	17,778	54,763	57,342
Services | Western Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	12,872	10,974	33,813	35,094
Services | Eastern Hemisphere | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	2,458	3,689	7,748	11,620
Services | Asia Pacific | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues	$ 4,230	$ 3,115
Services | Asia Pacific Segment | Operating Segments
Disaggregation Of Revenue [Line Items]
Revenues			$ 13,202	$ 10,628