Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Supplemental non-cash investing and financing activities:
Value of common stock issued in acquisitions	$ 3,268	$ 1,014
Exercise of stock options by common stock surrender	50	1,126
Supplemental cash payment information:
Interest paid	1,459	1,043
Income taxes paid, net of refunds	$ 1,663	$ 3,044