Income Taxes (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Income (Loss) from continuing operations
U.S. operations		$ 23,913	$ 7,465	$ 54,018
Foreign operations		11,929	(8,757)	12,473
Profit Before Income Taxes		35,842	(1,292)	66,491
Current:
Federal		3,731	2,590	15,962
Foreign		7,030	8,701	3,035
State		1,033	812	1,859
Current Income Tax Expense		11,794	12,103	20,856
Deferred:
Federal		(3,135)	1,640	(472)
Foreign		(6,012)	(8,699)	(434)
State		(343)	(131)	(73)
Deferred Income Tax Expense		(9,490)	(7,190)	(979)
Total:
Federal		596	4,230	15,490
Foreign		1,018	2	2,601
State		690	681	1,786
Total Income Tax Expense		$ 2,304	$ 4,913	$ 19,877
Operating loss carryforwards
Federal Statutory Income Tax Rate, Historical			35.00%
Tax Cuts and Jobs Act of 2017 Corporate Federal Tax Rate		21.00%
Tax loss carryforwards					$ 18,649
Tax credit carryforwards					4,708	$ 1,575
Effective income tax rate reconciliation
Tax at statutory rate		21.00%	35.00%	35.00%
Increases (decreases) in the tax rate from:
State and local taxes, net of federal benefit		1.40%	(21.10%)	1.70%
Effect of foreign operations		(4.30%)	(70.80%)	(5.50%)
Transaction costs		(4.20%)	(226.30%)	0.00%
Effect of 2017 deferred rate change		(1.00%)	(154.30%)	0.00%
Transition Tax	(1.30%)	(1.00%)	(28.00%)	0.00%
Effect of changes in valuation allowances		6.60%	(126.50%)	1.90%
Domestic production activities deduction		0.40%	28.30%	(2.20%)
Share-based payments		(5.70%)	90.40%	0.00%
Research & Development credit		(3.60%)	82.90%	(1.30%)
Other, net		(3.20%)	10.20%	0.30%
Effective income tax rate		6.40%	(380.20%)	29.90%
Deferred Tax Assets:
Inventories, principally due to changes in inventory reserves					3,335	4,757
Employee wages and benefits, principally due to accruals for financial reporting purposes					11,642	11,031
Warranty reserves accrued for financial reporting purposes					2,610	2,578
Receivable, principally due to allowance for doubtful accounts and tax accounting method for equipment rentals					1,728	2,138
Tax loss carryforwards					7,765	11,383
Tax credit carryforwards					4,708	1,575
Other					4,712	3,630
Gross Deferred Tax Assets					36,500	37,092
Less: valuation allowance					(11,519)	(9,691)
Total Net Deferred Tax Assets					24,981	27,401
Deferred Tax Liabilities:
Property, Plant and Equipment, principally due to differences in depreciation and related gains					9,882	9,042
Goodwill and Intangible Assets					45,628	60,450
Total Deferred Tax Liabilities					55,510	69,492
Net Deferred Tax Liabilities					(30,529)	(42,091)
Reconciliation of unrecognized tax benefits
Balance at January 1,	$ 2,232	$ 2,232	$ 2,477
Increases as a result of tax positions taken during the current year		370	329
Increases as a result of tax positions taken in prior period		74
Increase reslted to prior period tax positions of acquired entities		3,833	236
Decreases relating to settlement with tax authorities		0	(68)
Reductions as a result of a lapse of the applicable statute of limitations		(1,274)	(770)
Increases (Decreases) as a result of foreign currency fluctuations		418	28
Balance at December 31,		5,653	2,232	$ 2,477
Unrecognized tax benefits that would impact the effective tax rate					5,473	1,992
Unrecognized Tax Benefits	$ 2,232	$ 2,232	$ 2,477	$ 2,477	5,653	2,232
Accrued interest and penalties					416	$ 482
Minimum
Income Tax General Disclosure [Abstract]
Income Tax Examination, Year under Examination		2014
Maximum
Income Tax General Disclosure [Abstract]
Income Tax Examination, Year under Examination		2016
U.S.
Operating loss carryforwards
Tax credit carryforwards					1,268
Income Tax General Disclosure [Abstract]
Undistributed earnings of non-U.S. subsidiaries					1,572
Deferred Tax Assets:
Tax credit carryforwards					1,268
Dutch
Operating loss carryforwards
Foreign tax credit carryforwards					1,628
FOREIGN
Operating loss carryforwards
Tax loss carryforwards					35,593
Tax loss carryforwards expiration		$ 16,944
Foreign tax credit carryforwards					$ 1,812