Business Segments - Revenues (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Segment Reporting, Revenue Reconciling Item [Line Items]
Oil and natural gas	$ 14,717		$ 10,387
Revenues	745,921		567,404
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Oil and natural gas	14,717		10,387
Revenues	747,142		568,071
Operating Segments | Contract Drilling
Segment Reporting, Revenue Reconciling Item [Line Items]
Oil and gas services	490,703		378,025
Operating Segments | Pressure Pumping
Segment Reporting, Revenue Reconciling Item [Line Items]
Oil and gas services	241,722		179,659
Intersegment Elimination
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ (1,221)	[1]	$ (667)	[1]

[1] Consists of contract drilling intercompany revenues for drilling services provided to the oil and natural gas exploration and production segment.