Revenue - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Percentage of revenues derived from services provided			90.00%
Percentage of revenues derived from other sources			10.00%
Net increase to revenue for adjustments to fixed price contracts	$ 400,000	$ 400,000	$ 900,000	$ 1,300,000
Remaining performance obligations	286,400,000		286,400,000
Remaining performance obligation expected to be recognized in next 12 months, percentage	0.85		0.85
Disaggregation of Revenue [Line Items]
Remaining performance obligations	286,400,000		286,400,000
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Estimate of Transaction Price	400,000	400,000	900,000	1,300,000
Revenue recognized related to contract liabilities	$ 1,900,000	$ 1,500,000	$ 13,300,000	$ 17,200,000
Minimum
Disaggregation of Revenue [Line Items]
Bill and collection period			60 days
Maximum
Disaggregation of Revenue [Line Items]
Bill and collection period			120 days