Business Segments - Capital Expenditures (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Capital expenditures	$ 96,919	$ 194,862	$ 215,260	$ 317,783
Corporate
Segment Reporting Information [Line Items]
Capital expenditures	773	227	2,104	753
Operating Segments | Contract Drilling
Segment Reporting Information [Line Items]
Capital expenditures	47,664	121,095	123,389	196,342
Operating Segments | Pressure Pumping
Segment Reporting Information [Line Items]
Capital expenditures	38,802	56,195	70,202	81,118
Operating Segments | Directional Drilling
Segment Reporting Information [Line Items]
Capital expenditures	3,450	10,034	5,562	22,863
Other Operations
Segment Reporting Information [Line Items]
Capital expenditures	$ 6,230	$ 7,311	$ 14,003	$ 16,707