Accrued Liabilities (Tables)

3 Months Ended

Mar. 31, 2019

Payables and Accruals [Abstract]

Schedule of other accrued liabilities

The components of other accrued liabilities are as follows:

	As of
	March 31, 2019		December 31, 2018
Contract liabilities (Note 3)	$	902	$	1,234
Accrued remediation contingency (Note 14)	1,223		—
Other accrued liabilities	2,775		4,865
Total other accrued liabilities	$	4,900	$	6,099