Restatement of Previously Issued Consolidated Financial Statements - Effect of The Error Corrections On The Condensed Consolidated Statements of Cash Flow (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities:
Net Income	$ 4,178	$ 7,180	$ (32,913)	$ 23,312
Adjustments to reconcile net income to cash flows from operating activities:
Depreciation and amortization			13,835	10,865
Non-cash amortization of debt financing costs			1,365	1,030
Shared-based compensation expense			2,471	2,200
Deferred income taxes			(13,267)	1,840
Non-cash loss / (gain) on derivative contracts			2,038	2,092
Change in other operating items:
Accounts receivable			(13,686)	(20,454)
Inventories			(626)	1,191
Prepaid expenses			2,539	(2,607)
Accounts payable			26,856	3,272
Other operating activities, net			9,494	5,767
Net cash provided by operating activities			30,772	28,508
Cash Flows from Investing Activities:
Purchases of property, plant and equipment			(6,021)	(18,743)
Proceeds from disposal/sale of property, plant and equipment			569	20
Payments for acquisition of business			0	(34,000)
Net cash used in investing activities			(5,452)	(52,723)
Cash Flows from Financing Activities:
Borrowings on Revolving Credit Facility			15,000	8,500
Repayment of Revolving Credit Facility			(15,000)	(8,500)
Repayment of Term Loan			(8,281)	(6,338)
Other financing activities			(339)	(381)
Net cash used in financing activities			(11,199)	(6,719)
Effect of Foreign Currency Exchange Rate Changes on Cash			(31)	(1,276)
Net Decrease in Cash			14,090	(32,210)
Cash:
Beginning of period			39,511	70,913
End of period	$ 53,601	38,703	53,601	38,703
Supplemental Cash Flow Information:
Cash paid for interest			9,317	10,212
Cash paid for income taxes, net			906	5,530
Unpaid purchases of property and equipment included in accounts payable			$ 108	155
As Previously Reported
Cash Flows from Operating Activities:
Net Income		8,520		26,827
Adjustments to reconcile net income to cash flows from operating activities:
Depreciation and amortization				10,976
Non-cash amortization of debt financing costs				1,030
Shared-based compensation expense				2,200
Deferred income taxes				2,903
Non-cash loss / (gain) on derivative contracts				2,092
Change in other operating items:
Accounts receivable				(19,765)
Inventories				1,191
Prepaid expenses				(7,458)
Accounts payable				3,272
Other operating activities, net				5,767
Net cash provided by operating activities				29,035
Cash Flows from Investing Activities:
Purchases of property, plant and equipment				(19,270)
Proceeds from disposal/sale of property, plant and equipment				20
Payments for acquisition of business				(34,000)
Net cash used in investing activities				(53,250)
Cash Flows from Financing Activities:
Borrowings on Revolving Credit Facility				8,500
Repayment of Revolving Credit Facility				(8,500)
Repayment of Term Loan				(6,338)
Other financing activities				(381)
Net cash used in financing activities				(6,719)
Effect of Foreign Currency Exchange Rate Changes on Cash				(1,276)
Net Decrease in Cash				(32,210)
Cash:
Beginning of period				70,913
End of period		38,703		38,703
Supplemental Cash Flow Information:
Cash paid for interest				10,212
Cash paid for income taxes, net				5,530
Unpaid purchases of property and equipment included in accounts payable				155
Restatement Adjustments
Cash Flows from Operating Activities:
Net Income		(1,340)		(3,515)
Adjustments to reconcile net income to cash flows from operating activities:
Depreciation and amortization				(111)
Non-cash amortization of debt financing costs				0
Shared-based compensation expense				0
Deferred income taxes				(1,063)
Non-cash loss / (gain) on derivative contracts				0
Change in other operating items:
Accounts receivable				(689)
Inventories				0
Prepaid expenses				4,851
Accounts payable				0
Other operating activities, net				0
Net cash provided by operating activities				(527)
Cash Flows from Investing Activities:
Purchases of property, plant and equipment				527
Proceeds from disposal/sale of property, plant and equipment				0
Payments for acquisition of business				0
Net cash used in investing activities				527
Cash Flows from Financing Activities:
Borrowings on Revolving Credit Facility				0
Repayment of Revolving Credit Facility				0
Repayment of Term Loan				0
Other financing activities				0
Net cash used in financing activities				0
Effect of Foreign Currency Exchange Rate Changes on Cash				0
Net Decrease in Cash				0
Cash:
Beginning of period				0
End of period		$ 0		0
Supplemental Cash Flow Information:
Cash paid for interest				0
Cash paid for income taxes, net				0
Unpaid purchases of property and equipment included in accounts payable				$ 0