General - Contingent Consideration (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2018
Fair value measurement of contingent consideration
Estimated undiscounted future contingent payments	$ 100		$ 100			$ 10,600
Fair value of short-term contingent consideration	119		119			8,000
Fair value of long-term contingent consideration						$ 2,124
Liability for contingent consideration
Balance as of beginning of period			10,124
Changes in fair value	(2,149)	$ 70	(2,005)	$ 303
Payments			(8,000)
Balance as of end of period	$ 119		$ 119
Forecast
Fair value measurement of contingent consideration
Estimated undiscounted future contingent payments					$ 100