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Revenue Recognition (Details 1)
3 Months Ended
Mar. 31, 2021
USD ($)
Revenue Recognition [Abstract]  
Deferred revenue, beginning $ 180,000
Reclassification of beginning deferred revenue to revenue, as a result of performance obligations satisfied (132,000)
Cash received in advance and not recognized as revenue 652,000
Deferred revenue, ending $ 700,000