Selected Quarterly Financial Data (Unaudited) - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	[1]	Dec. 31, 2018	Dec. 31, 2017	[2]
Selected Quarterly Financial Data [Line Items]
Gain on minority investment	$ 13,000
Loss on write-off of fixed assets	1,800	$ 8,800	$ 1,819		$ 8,793	$ 0
Legal settlement		5,500
Restructuring charges	$ 2,800	1,100
Chevron | Disposed of by Sale
Selected Quarterly Financial Data [Line Items]
Gain on disposal		$ 152,800

[1] Reflects the impact of the Company's adoption of ASU 2016-02 "Leases", on January 1, 2019 using the modified retrospective transition method. The adoption of the Leases guidance resulted in an adjustment to other assets, other current liabilities and other noncurrent liabilities in our consolidated balance sheet for the cumulative effect of applying the standard. Financial results reported in periods prior to 2019 are unchanged.

[2] Reflects the impact of the Company's adoption of Accounting Standards Update 2016-18, Statement of Cash Flows (Topic 230), which was adopted by the Company on January 1, 2018 and applied retrospectively to results for 2017. The adoption of Topic 230 resulted in the statement of cash flows presenting the changes in the total of cash, cash equivalents and restricted cash. As a result, the Company will no longer present transfers between cash and cash equivalents and restricted cash in the statement of cash flows.