Segment Reporting (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment									3
Revenue, Net	$ 149,542	$ 143,483	$ 148,069	$ 153,647	$ 182,723	$ 197,265	$ 203,889	$ 213,643	$ 594,741	$ 797,520	$ 1,085,222
Segment Reporting Information, Intersegment Revenue									0	0	0
Income Before Interest Expense and Taxes	21,524	$ 21,488	$ 20,227	$ 22,940	23,642	$ 46,818	$ 47,893	$ 42,717	86,179	161,070	346,531
Assets	573,052				625,258				573,052	625,258	673,325
Payments to Acquire Property, Plant, and Equipment									11,356	22,797	36,586
Depreciation and amortization									26,872	27,457	26,696
Operating Segment Reservoir Description [Member]
Segment Reporting Information [Line Items]
Revenue, Net									404,146	473,372	518,974
Segment Reporting Information, Intersegment Revenue									3,941	8,674	10,387
Income Before Interest Expense and Taxes									75,148	111,032	143,624
Assets	301,574				326,182				301,574	326,182	319,325
Payments to Acquire Property, Plant, and Equipment									8,195	17,849	21,371
Depreciation and amortization									17,735	16,778	15,816
Operating Segment Production Enhancement [Member]
Segment Reporting Information [Line Items]
Revenue, Net									164,027	267,224	467,577
Segment Reporting Information, Intersegment Revenue									877	1,837	2,459
Income Before Interest Expense and Taxes									8,891	35,027	165,204
Assets	191,846				210,214				191,846	210,214	257,135
Payments to Acquire Property, Plant, and Equipment									2,298	3,292	7,990
Depreciation and amortization									5,272	6,611	7,509
Operating Segment Reservoir Management [Member]
Segment Reporting Information [Line Items]
Revenue, Net									26,568	56,924	98,671
Segment Reporting Information, Intersegment Revenue									121	248	366
Income Before Interest Expense and Taxes									2,043	15,655	37,220
Assets	17,599				27,076				17,599	27,076	34,179
Payments to Acquire Property, Plant, and Equipment									25	273	2,681
Depreciation and amortization									1,344	1,624	1,393
Operating Segment Corporate And Other [Member]
Segment Reporting Information [Line Items]
Revenue, Net									0	0	0
Segment Reporting Information, Intersegment Revenue									(4,939)	(10,759)	(13,212)
Income Before Interest Expense and Taxes									97	(644)	483
Assets	$ 62,033				$ 61,786				62,033	61,786	62,686
Payments to Acquire Property, Plant, and Equipment									838	1,383	4,544
Depreciation and amortization									$ 2,521	$ 2,444	$ 1,978