Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2018

Supplemental Cash Flow Elements [Abstract]

Components of supplemental cash flow information

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

	Year ended December 31,
	2018			2017			2016
Supplemental non-cash investing and financing activities:
Value of common stock issued in acquisitions	$	—		$	—		$	3,268
Value of common stock issued in payment of accrued liability	—			188			—
Exercise of stock options by common stock surrender	—			5,863			50
Supplemental cash payment information:
Interest paid	$	2,502		$	1,851		$	2,024
Income taxes (received, net of payments) paid, net of refunds	(139		)	(10,195		)	333