Investments (Details) - USD ($)	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Cost method investment	$ 3,440,000	$ 3,440,000
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	200,000
Impairment of equity method investments	0
Digital Construction Works, Inc. \| Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 174,000	$ 2,251,000
Ownership percentage	50.00%
Digital Construction Works, Inc. \| Topcon
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Seequent
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 2,234,000

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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