Organization and Basis of Presentation - Additional Information (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) Segment Vessel	Sep. 30, 2016 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of jackups | Vessel	14
Number of drillships | Vessel	8
Number of semisubmersibles | Vessel	6
Number of reportable segments | Segment	1
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating activities in Consolidated Statement of Cash Flows	$ 299,080	$ 960,368
Financing activities in Consolidated Statement of Cash Flows	$ (330,645)	(436,678)
Accounting Standards Update 2016-09, Excess Tax Benefit Component [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating activities in Consolidated Statement of Cash Flows		5,500
Financing activities in Consolidated Statement of Cash Flows		(5,500)
Accounting Standards Update 2016-09, Statutory Tax Withholding Component [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating activities in Consolidated Statement of Cash Flows		(3,200)
Financing activities in Consolidated Statement of Cash Flows		$ 3,200