Business Segments - Identifiable Assets (Detail) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Asset Reconciling Item [Line Items]
Total assets		$ 4,439,615	$ 5,469,866	$ 5,758,856
Corporate
Segment Reporting Asset Reconciling Item [Line Items]
Total assets	[1]	261,019	314,276	144,069
Operating Segments | Contract Drilling
Segment Reporting Asset Reconciling Item [Line Items]
Total assets		3,190,463	3,817,638	3,931,994
Operating Segments | Pressure Pumping
Segment Reporting Asset Reconciling Item [Line Items]
Total assets		695,570	921,237	1,209,424
Operating Segments | Directional Drilling
Segment Reporting Asset Reconciling Item [Line Items]
Total assets		164,273	239,341	301,275
Other Operations
Segment Reporting Asset Reconciling Item [Line Items]
Total assets		$ 128,290	$ 177,374	$ 172,094

[1] Corporate assets primarily include cash on hand and certain property and equipment.