Revenue - Disaggregation of Revenue - Expected Timing Of Satisfaction Period (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 3,800	$ 4,196	$ 3,800	$ 4,196
Revenue from divested businesses	0	0	0	4,300
Disposal Group, Including Discontinued Operation, Revenue	0	$ 0	0	$ 4,300
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 1,509		$ 1,509
Revenue, remaining performance obligation, expected timing of satisfaction, period	12 months		12 months