Joint Ventures (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Jun. 30, 2019	Dec. 31, 2018
Assets:
Accounts receivable			$ 737,353	$ 756,320
Other current assets			147,239	177,604
Property, plant and equipment, net			5,301,252	5,467,870
Other long-term assets			298,660	263,506
Total assets (1)	[1]		7,514,503	7,853,944
Liabilities:
Accounts payable			410,469	392,843
Accrued liabilities			319,763	417,912
Total liabilities (1)	[1]		4,644,320	4,698,757
SANAD
Assets:
Cash and cash equivalents			230,352	211,618
Accounts receivable			81,440	73,699
Other current assets			21,236	17,198
Property, plant and equipment, net			443,643	457,963
Other long-term assets			16,490	36,583
Total assets (1)			793,161	797,061
Liabilities:
Accounts payable			65,655	60,087
Accrued liabilities			14,367	8,530
Total liabilities (1)			$ 80,022	$ 68,617
Saudi Aramco | SANAD
Joint Ventures
Cash contribution for joint venture		$ 20,000
Additional contribution amount		$ 394,000
Maturity period		25 years

[1] The condensed consolidated balance sheet as of June 30, 2019 and December 31, 2018 include assets and liabilities of variable interest entities. See Note 3—Joint Ventures for additional information.