Investments (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Payments to acquire cost method investments	$ 3,440,000
Payments to acquire equity method investments	3,000,000
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Equity method investments	2,251,000	$ 1,725,000
Impairment of equity method investments	$ 0
Digital Construction Works, Inc. \| Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Digital Construction Works, Inc. \| Topcon
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%

Payments To Acquire Cost Method Investments

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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.

+ References

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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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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