Quarterly report pursuant to Section 13 or 15(d)

Revenue Contract Assets and Liabilities (Details)

v3.20.2
Revenue Contract Assets and Liabilities (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2019
Revenue from Contract with Customer [Abstract]          
Contract assets $ 948,000   $ 948,000   $ 1,089,000
Contract with customer, liability 15,100,000   15,100,000   $ 11,600,000
Contract with customer, liability, revenue recognized $ 3,900,000 $ 3,700,000 6,600,000 $ 6,300,000  
Contract with customer, performance obligation satisfied in previous period     $ 0 $ 0