Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Inventory [Line Items]
Raw materials:	$ 116,536	$ 134,591
Total inventories	143,612	163,657
Asset impairment charges	12,523	75,508	$ 0
Drilling fluids
Inventory [Line Items]
Raw materials:	115,399	133,934
Mats
Inventory [Line Items]
Raw materials:	1,137	657
Finished goods	3,314	3,723
Blended drilling fluids components
Inventory [Line Items]
Finished goods	23,762	25,343
Total inventories	143,612	$ 163,657
Cost of sales [Member]
Inventory [Line Items]
Asset impairment charges	$ 4,100