Supplemental Guarantor Financial Information Supplemental Guarantor Financial Information (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	$ 44,819	$ 29,135	$ 31,109
Investing activities:
Purchases of property, plant, and equipment, net	(48,137)	(24,574)	(20,947)
Acquisition of CSI	(825,000)
Advances and other investing activities	(805)	0	(39)
Net cash used in investing activities	(873,942)	(24,574)	(20,986)
Financing activities:
Proceeds from long-term debt, net	602,858	19,909	10,050
Payments of long-term debt	(93,584)	0	0
Proceeds from issuance of partnership common units, net of underwriters' discount	395,794	0	0
Distributions	(36,687)	(26,969)	(24,732)
Financing costs	(22,486)	916
Intercompany contribution (distribution)	0	0	0
Intercompany loan activity	0	0	0
Contribution from general partner	8,405
Net cash (used in) provided by financing activities	854,300	(7,976)	(14,682)
Effect of exchange rate changes on cash	(588)	(74)	49
Increase (decrease) in cash and cash equivalents	24,589	(3,489)	(4,510)
Cash and cash equivalents at beginning of period	9,477	12,966	17,476
Cash and cash equivalents at end of period	34,066	9,477	12,966
Issuers [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	14,688	0	0
Investing activities:
Purchases of property, plant, and equipment, net	0	0	0
Acquisition of CSI	0
Advances and other investing activities			0
Net cash used in investing activities	(367,512)	26,969	24,732
Financing activities:
Proceeds from long-term debt, net	344,961	0	0
Payments of long-term debt	0
Proceeds from issuance of partnership common units, net of underwriters' discount	395,794
Distributions	(36,687)	(26,969)	(24,732)
Financing costs	(9,649)	0
Intercompany contribution (distribution)	0	0	0
Intercompany loan activity	(350,000)	0	0
Contribution from general partner	8,405
Net cash (used in) provided by financing activities	352,824	(26,969)	(24,732)
Effect of exchange rate changes on cash	0	0	0
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of period	0	0	0
Cash and cash equivalents at end of period	0	0	0
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	22,767	21,733	32,677
Investing activities:
Purchases of property, plant, and equipment, net	(44,313)	(19,263)	(18,658)
Acquisition of CSI	(825,000)
Advances and other investing activities	(805)		(39)
Net cash used in investing activities	(872,751)	(19,263)	(18,697)
Financing activities:
Proceeds from long-term debt, net	257,897	19,909	10,050
Payments of long-term debt	(93,584)
Proceeds from issuance of partnership common units, net of underwriters' discount	0
Distributions	0	0	0
Financing costs	(12,837)	916
Intercompany contribution (distribution)	367,512	(26,969)	(24,732)
Intercompany loan activity	350,000	291	2,746
Contribution from general partner	0
Net cash (used in) provided by financing activities	868,988	(7,685)	(11,936)
Effect of exchange rate changes on cash	0	0	0
Increase (decrease) in cash and cash equivalents	19,004	(5,215)	2,044
Cash and cash equivalents at beginning of period	4,339	9,554	7,510
Cash and cash equivalents at end of period	23,343	4,339	9,554
Other Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	7,364	7,402	(1,568)
Investing activities:
Purchases of property, plant, and equipment, net	(3,824)	(5,311)	(2,289)
Acquisition of CSI	0
Advances and other investing activities	0		0
Net cash used in investing activities	(3,824)	(5,311)	(2,289)
Financing activities:
Proceeds from long-term debt, net	0	0	0
Payments of long-term debt	0
Proceeds from issuance of partnership common units, net of underwriters' discount	0
Distributions	0	0	0
Financing costs	0
Intercompany contribution (distribution)	2,633	0	0
Intercompany loan activity	0	(291)	(2,746)
Contribution from general partner	0
Net cash (used in) provided by financing activities	2,633	(291)	(2,746)
Effect of exchange rate changes on cash	(588)	(74)	49
Increase (decrease) in cash and cash equivalents	5,585	1,726	(6,554)
Cash and cash equivalents at beginning of period	5,138	3,412	9,966
Cash and cash equivalents at end of period	10,723	5,138	3,412
Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	0	0	0
Investing activities:
Purchases of property, plant, and equipment, net	0	0	0
Acquisition of CSI	0
Advances and other investing activities			0
Net cash used in investing activities	370,145	(26,969)	(24,732)
Financing activities:
Proceeds from long-term debt, net	0	0	0
Payments of long-term debt	0
Proceeds from issuance of partnership common units, net of underwriters' discount	0
Distributions	0	0	0
Financing costs	0	0
Intercompany contribution (distribution)	(370,145)	26,969	24,732
Intercompany loan activity	0	0	0
Contribution from general partner	0
Net cash (used in) provided by financing activities	(370,145)	26,969	24,732
Effect of exchange rate changes on cash	0	0	0
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of period	0	0	0
Cash and cash equivalents at end of period	$ 0	$ 0	$ 0