Revenues - Major Product Line (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	$ 1,341
Rental Revenues	82
Total Revenues	1,423	$ 1,386
Production
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	381
Rental Revenues	0
Total Revenues	381
Completions
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	293
Rental Revenues	1
Total Revenues	294
Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	350
Rental Revenues	8
Total Revenues	358
Well Construction
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	317
Rental Revenues	73
Total Revenues	390
Western Hemisphere
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	700
Western Hemisphere | Production
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	286
Western Hemisphere | Completions
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	157
Western Hemisphere | Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	156
Western Hemisphere | Well Construction
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	101
Eastern Hemisphere
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	641
Eastern Hemisphere | Production
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	95
Eastern Hemisphere | Completions
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	136
Eastern Hemisphere | Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	194
Eastern Hemisphere | Well Construction
Disaggregation of Revenue [Line Items]
Total Excluding Rental Revenues	$ 216