Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2013

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

	Three months ended					Six months ended
	June 30, 2013		June 30, 2012			June 30, 2013		June 30, 2012
Supplemental disclosures:	(in thousands)
Interest paid	$	—	$	2		$	—	$	26
Income taxes paid	5,904		3,700			6,089		3,700
Non-cash investing and financing activities:
Non-cash capital expenditures	274		(2,750		)	290		(1,356		)
Trade-in of equipment	—		—			—		300