Property and Equipment - Components of property and equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant And Equipment [Line Items]
Property and equipment, gross	$ 682,469	$ 661,619
Less accumulated depreciation and amortization	275,591	212,818
Property and equipment, net	406,878	448,801
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	81,929
Property and equipment, at cost		102,852
Less accumulated depreciation	30,000
Less accumulated depreciation		31,954
Property and equipment under finance lease, net	51,929
Property and equipment under finance lease, net		70,898
Land
Property, Plant And Equipment [Line Items]
Property and equipment, gross	20,351	21,431
Buildings and improvements
Property, Plant And Equipment [Line Items]
Property and equipment, gross	40,392	40,524
Well service units and equipment
Property, Plant And Equipment [Line Items]
Property and equipment, gross	130,300	122,694
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	0
Property and equipment, at cost		199
Fracturing/test tanks
Property, Plant And Equipment [Line Items]
Property and equipment, gross	119,999	123,550
Pumping equipment
Property, Plant And Equipment [Line Items]
Property and equipment, gross	102,294	103,689
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	22,958
Property and equipment, at cost		48,929
Fluid services equipment
Property, Plant And Equipment [Line Items]
Property and equipment, gross	79,426	78,524
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	35,595
Property and equipment, at cost		35,034
Disposal facilities
Property, Plant And Equipment [Line Items]
Property and equipment, gross	83,655	63,229
Rental equipment
Property, Plant And Equipment [Line Items]
Property and equipment, gross	65,775	62,642
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	1,131
Property and equipment, at cost		0
Light vehicles
Property, Plant And Equipment [Line Items]
Property and equipment, gross	30,563	27,080
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	22,245
Property and equipment, at cost		18,376
Brine and fresh water stations
Property, Plant And Equipment [Line Items]
Property and equipment, gross	4,374	3,296
Software
Property, Plant And Equipment [Line Items]
Property and equipment, gross	925	857
Other
Property, Plant And Equipment [Line Items]
Property and equipment, gross	4,415	4,257
Contract drilling equipment
Property, Plant And Equipment [Line Items]
Property and equipment, gross	0	9,846
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Property and equipment, at cost	$ 0
Property and equipment, at cost		$ 314