Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2018

Supplemental Cash Flow Elements [Abstract]

Components of supplemental cash flow information

Supplemental cash flow information is as follows (in thousands):

	Six months ended June 30,
	2018		2017
Supplemental non-cash investing and financing activities:
Value of common stock issued in payment of accrued liability	$	—	$	188
Exercise of stock options by common stock surrender	—		5,814
Supplemental cash payment information:
Interest paid	$	983	$	1,069
Income taxes paid, net of refunds (received, net of payments)	327		(9,489		)