Supplemental Guarantor Financial Information Supplemental Guarantor Financial Information (Statement of Cash Flows) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	$ 24,572	$ 45,522
Investing activities:
Purchases of property, plant, and equipment, net	(13,713)	(7,602)
Insurance recoveries	2,352	0
Intercompany investment activity	0	0
Advances and other investing activities	25	20
Net cash used in investing activities	(11,336)	(7,582)
Financing activities:
Proceeds from long-term debt, net	66,300	53,000
Payments of long-term debt	(64,900)	(125,800)
Proceeds from Issuance of Common Limited Partners Units		77,321
Proceeds from Convertible Debt	(37)	77,300
Distributionstononcontrollingholders	(26,152)	(38,366)
Financing costs	(1,690)	(840)
Intercompany contribution (distribution)	0	0
Net cash used in financing activities	(26,479)	(34,685)
Effect of exchange rate changes on cash	(176)	(522)
Increase (decrease) in cash and cash equivalents	(13,419)	2,733
Cash and cash equivalents at beginning of period	20,797	10,620
Cash and cash equivalents at end of period	7,378	13,353
Parent Company [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	0	(58,521)
Investing activities:
Purchases of property, plant, and equipment, net	0	0
Insurance recoveries	0
Intercompany investment activity	26,271	38,366
Advances and other investing activities	0	0
Net cash used in investing activities	26,271	38,366
Financing activities:
Proceeds from long-term debt, net	0	0
Payments of long-term debt	0	(18,800)
Proceeds from Issuance of Common Limited Partners Units		77,321
Proceeds from Convertible Debt	(37)
Distributionstononcontrollingholders	(26,152)	(38,366)
Financing costs	(82)	0
Intercompany contribution (distribution)	0	0
Net cash used in financing activities	(26,271)	20,155
Effect of exchange rate changes on cash	0	0
Increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	29,445	101,259
Investing activities:
Purchases of property, plant, and equipment, net	(14,086)	(6,158)
Insurance recoveries	2,352
Intercompany investment activity	0	0
Advances and other investing activities	25	20
Net cash used in investing activities	(11,709)	(6,138)
Financing activities:
Proceeds from long-term debt, net	66,300	53,000
Payments of long-term debt	(64,900)	(107,000)
Proceeds from Issuance of Common Limited Partners Units		0
Proceeds from Convertible Debt	0
Distributionstononcontrollingholders	0	0
Financing costs	(1,608)	(840)
Intercompany contribution (distribution)	(26,271)	(38,366)
Net cash used in financing activities	(26,479)	(93,206)
Effect of exchange rate changes on cash	0	0
Increase (decrease) in cash and cash equivalents	(8,743)	1,915
Cash and cash equivalents at beginning of period	12,201	2,711
Cash and cash equivalents at end of period	3,458	4,626
Other Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	(4,873)	2,784
Investing activities:
Purchases of property, plant, and equipment, net	373	(1,444)
Insurance recoveries	0
Intercompany investment activity	0	0
Advances and other investing activities	0
Net cash used in investing activities	373	(1,444)
Financing activities:
Proceeds from long-term debt, net	0	0
Payments of long-term debt	0	0
Proceeds from Issuance of Common Limited Partners Units		0
Proceeds from Convertible Debt	0
Distributionstononcontrollingholders	0	0
Financing costs	0	0
Intercompany contribution (distribution)	0	0
Net cash used in financing activities	0	0
Effect of exchange rate changes on cash	(176)	(522)
Increase (decrease) in cash and cash equivalents	(4,676)	818
Cash and cash equivalents at beginning of period	8,596	7,909
Cash and cash equivalents at end of period	3,920	8,727
Consolidation, Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	0	0
Investing activities:
Purchases of property, plant, and equipment, net	0	0
Insurance recoveries	0
Intercompany investment activity	(26,271)	(38,366)
Advances and other investing activities	0	0
Net cash used in investing activities	(26,271)	(38,366)
Financing activities:
Proceeds from long-term debt, net	0	0
Payments of long-term debt	0	0
Proceeds from Issuance of Common Limited Partners Units		0
Proceeds from Convertible Debt	0
Distributionstononcontrollingholders	0	0
Financing costs	0	0
Intercompany contribution (distribution)	26,271	38,366
Net cash used in financing activities	26,271	38,366
Effect of exchange rate changes on cash	0	0
Increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0