Supplemental Cash Flow Information (Tables)

9 Months Ended

Sep. 30, 2018

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

	Nine months ended
	September 30, 2018		September 30, 2017
Supplemental disclosures:	(in thousands)
Interest paid	$	5	$	—
Income taxes paid	$	9,183	$	7,138
Non-cash investing and financing activities:
Non-cash capital expenditures	$	288	$	8,059