Cash and Cash Equivalents (Tables)

6 Months Ended

Jun. 30, 2018

Cash and Cash Equivalents [Abstract]

Cash and cash equivalents

The carrying values of the Company's cash and cash equivalents are as follows:

	As of June 30,		As of December 31,
	2018		2017
	(in thousands)
	(unaudited)
Cash	$	103,690	$	70,459
Cash equivalents	41,769		193,315
Restricted cash - letters of credit	3,827		3,872
Total cash and cash equivalents	$	149,286	$	267,646