Revenue Contract Balances (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue [Abstract]
Contract with Customer, Performance Obligation Satisfied in Previous Period	$ 0	$ 0	$ 0
Contract assets	467,000	1,089,000
Contract with Customer, Liability		$ 16,400,000	$ 11,600,000
Contract with Customer, Liability, Revenue Recognized	9,800,000
Revenue, Remaining Performance Obligation, Amount	$ 28,300,000
Revenue, Performance Obligation, Description of Timing	30 to 60 days