菜創郭肱利 Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Adoption of New Accounting Standards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	油	油	油
Operating income	$ 260,834	$ 144,947	$ 62,911
Other income (expense)	$ 916	114	(15)
As reported in prior year	油	油	油
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	油	油	油
Operating income	油	119,776	55,058
Other income (expense)	油	84	29
Accounting Standards Update 2017-07 \| Retrospective adjustment	油	油	油
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	油	油	油
Operating income	油	25,171	7,853
Other income (expense)	油	$ 30	$ (44)