Segment Reporting Revenue by Product Sales and Services (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenue from External Customer [Line Items]
Sales Revenue, Services, Net									$ 621,752,000	$ 568,220,000	$ 529,523,000
Sales Revenue, Goods, Net									285,896,000	226,433,000	166,016,000
Revenue, Net	243,786,000	231,344,000	225,785,000	206,733,000	208,193,000	199,221,000	198,902,000	188,337,000	907,648,000	794,653,000	695,539,000
Operating Segment Reservoir Description [Member]
Revenue from External Customer [Line Items]
Sales Revenue, Services, Net									443,050,000	403,443,000	395,374,000
Sales Revenue, Goods, Net									26,725,000	22,386,000	19,560,000
Revenue, Net									469,775,000	425,829,000	414,934,000
Operating Segment Production Enhancement [Member]
Revenue from External Customer [Line Items]
Sales Revenue, Services, Net									129,400,000	122,046,000	97,569,000
Sales Revenue, Goods, Net									242,049,000	191,910,000	133,083,000
Revenue, Net									371,449,000	313,956,000	230,652,000
Operating Segment Reservoir Management [Member]
Revenue from External Customer [Line Items]
Sales Revenue, Services, Net									49,302,000	42,731,000	36,580,000
Sales Revenue, Goods, Net									17,122,000	12,137,000	13,373,000
Revenue, Net									$ 66,424,000	$ 54,868,000	$ 49,953,000