Reportable Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]
Sales	$ 266,240	$ 273,648
Operating Income (Loss)	22,146	27,351
Energy & Chemicals [Member]
Segment Reporting Information [Line Items]
Sales	86,146	80,861
Operating Income (Loss)	16,607	12,819
Distribution & Storage [Member]
Segment Reporting Information [Line Items]
Sales	129,522	128,733
Operating Income (Loss)	18,087	19,289
BioMedical [Member]
Segment Reporting Information [Line Items]
Sales	50,572	64,054
Operating Income (Loss)	2,395	6,753
Corporate [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ (14,943)	$ (11,510)