Segment Disclosure - Financial Information (Details) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment													3
Financial information by segment
Revenues	$ 160,777	$ 147,894	$ 124,435	$ 159,465	$ 178,991	$ 192,192	$ 200,616	$ 176,787	$ 180,762	$ 182,169	$ 191,793	$ 187,630	$ 592,571	$ 748,586	$ 742,354
Gross profit	49,345	47,384	41,158	40,644	50,583	57,769	60,071	48,874	52,315	52,332	55,083	48,144	178,531	217,297	207,874
Operating Income (Loss)	4,652	$ 5,742	$ (383)	$ (111,228)	2,335	$ 10,779	$ 15,419	$ (4,396)	$ 2,502	$ 3,017	$ 10,304	$ 6,398	(101,217)	24,137	22,221
Depreciation and amortization													35,705	38,533	34,413
Intangible assets, net	68,642				109,537								68,642	109,537
Total assets	583,313				719,878								583,313	719,878
Operating segments | Services
Financial information by segment
Revenues													476,164	595,130	574,619
Gross profit													141,084	165,513	151,974
Operating Income (Loss)													(44,222)	49,593	47,126
Depreciation and amortization													26,093	28,854	24,079
Intangible assets, net	58,917				98,284								58,917	98,284
Total assets	427,636				537,518								427,636	537,518
Operating segments | International
Financial information by segment
Revenues													107,556	144,271	153,448
Gross profit													31,046	43,145	45,464
Operating Income (Loss)													(21,855)	5,856	3,953
Depreciation and amortization													8,659	8,285	8,846
Intangible assets, net	8,664				9,814								8,664	9,814
Total assets	129,228				153,380								129,228	153,380
Operating segments | Products and Systems
Financial information by segment
Revenues													16,449	18,583	23,426
Gross profit													6,826	8,639	10,560
Operating Income (Loss)													(936)	(529)	2,368
Depreciation and amortization													998	1,213	1,429
Intangible assets, net	1,012				1,181								1,012	1,181
Total assets	10,996				16,028								10,996	16,028
Corporate and eliminations
Financial information by segment
Revenues													(7,598)	(9,398)	(9,139)
Gross profit													(425)	0	(124)
Operating Income (Loss)													(34,204)	(30,783)	(31,226)
Depreciation and amortization													(45)	181	$ 59
Intangible assets, net	49				258								49	258
Total assets	$ 15,453				$ 12,952								$ 15,453	$ 12,952