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Investments (Details) - USD ($)	1 Months Ended	9 Months Ended
Investments (Details) - USD ($)	Aug. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Cost method investment		$ 3,376,000		$ 3,440,000
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments		500,000	$ 1,500,000
Impairment of equity method investments		0
Software Company
Schedule of Equity Method Investments [Line Items]
Cost method investment		$ 2,006,000
Software Company \| Convertible senior notes
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	$ 2,000,000
Digital Construction Works, Inc. \| Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Ownership percentage		50.00%
Equity method investments		$ 0		$ 2,251,000
Digital Construction Works, Inc. \| Topcon
Schedule of Equity Method Investments [Line Items]
Ownership percentage		50.00%