Restructuring (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		$ 8,800	$ 1,374	$ 0
Inventory write-down related to restructuring		7,400	7,408	0
Severance costs		1,400
Restructuring costs		882	882	0
Restructuring Reserve [Roll Forward]
Restructuring costs, beginning balance			0
Amount charged to operating expenses			1,374
Cash payments			(492)
Restructuring costs, ending balance		$ 882	$ 882	$ 0
Scenario, Forecast
Restructuring Cost and Reserve [Line Items]
Severance costs	$ 800