Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2019

Supplemental Cash Flow Elements [Abstract]

Components of supplemental cash flow information

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

	Years ended December 31,
	2019			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	—			—			5,863
Supplemental cash payment information:
Interest paid	$	599		$	2,502		$	1,851
Income taxes (received, net of payments) paid, net of refunds	(699		)	(139		)	(10,195		)