Revenues - Major Product Line (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues		$ 1,341
Rental Revenues	$ 78	82
Total Revenues	1,346	1,423
Production
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	391	381
Completions
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	305	293
Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	326	350
Well Construction
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	246	317
606 revenue [Member]
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	1,268	1,341
Western Hemisphere
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	669	700
Western Hemisphere | Production
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	295	286
Western Hemisphere | Completions
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	133	157
Western Hemisphere | Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	142	156
Western Hemisphere | Well Construction
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	99	101
Eastern Hemisphere
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	599	641
Eastern Hemisphere | Production
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	96	95
Eastern Hemisphere | Completions
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	172	136
Eastern Hemisphere | Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	184	194
Eastern Hemisphere | Well Construction
Disaggregation of Revenue [Line Items]
Total Revenues Excluding Rental Revenues	$ 147	$ 216