Selected Quarterly Financial Data (Unaudited) - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2018	[1]	Dec. 31, 2017		Dec. 31, 2016
Selected Quarterly Financial Data [Line Items]
Write-off of fixed assets	$ 8,800			$ 8,793		$ 0	[1]	$ 0	[1]
Tax benefit related to change in enacted tax rate		$ 128,200
Legal settlement	5,500	11,000
Restructuring charges	5,000
Non-cash stock based compensation expense		31,800		$ 69,939		93,297	[1]	63,946	[1]
Masternaut
Selected Quarterly Financial Data [Line Items]
Non-cash impairment charge on equity method investment		$ 36,100	$ 44,600			$ 44,600		$ 36,100
Chevron | Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Selected Quarterly Financial Data [Line Items]
Gain on disposal	$ 152,800

[1] 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.