Supplemental Cash Flow Information (Tables)

3 Months Ended

Mar. 31, 2018

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

	Three months ended
	March 31, 2018		March 31, 2017
Supplemental disclosures:	(in thousands)
Interest paid	$	5	$	—
Income taxes paid	$	6,232	$	361
Non-cash investing and financing activities:
Non-cash capital expenditures	$	733	$	1,098
Dividends declared	—		—