Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Contract Balances (Details)

v3.21.2
Summary of Significant Accounting Policies - Contract Balances (Details) - USD ($)
6 Months Ended
Jun. 30, 2021
Dec. 31, 2020
Summary of Significant Accounting Policies    
Contract liabilities $ 1,486,000 $ 373,000
Revenue included in contract balances $ 373,000