General - Contingent Consideration (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2020	Dec. 31, 2018
Fair value measurement of contingent consideration
Estimated undiscounted future contingent payments	$ 2,600			$ 10,600
Fair value of short-term contingent consideration				8,000
Fair value of long-term contingent consideration	2,268			$ 2,124
Liability for contingent consideration
Balance as of beginning of period	10,124
Changes in fair value	144	$ 233
Payments	(8,000)
Balance as of end of period	$ 2,268
Forecast
Fair value measurement of contingent consideration
Estimated undiscounted future contingent payments			$ 2,600