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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Summary of significant accounting policies (Details Narrative)	12 Months Ended
	Dec. 31, 2021 USD ($) shares	Dec. 31, 2021 CNY (¥) shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2020 CNY (¥) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)	Mar. 03, 2021 shares	Oct. 08, 2019 shares
Research and development costs	$ 61,000		$ 497,000		$ 35,000
Advertising and promotional expenses	7,000		7,000		$ 13,000
Unrecognized contract revenue	$ 5,400,000		$ 11,581,000
Shares issued \| shares	5,322,459	5,322,459	3,260,559	3,260,559			2,061,900	1,030,950
Accounts Receivable
Concentration percentage	10.00%	10.00%
Revenue
Concentration percentage	15.00%	15.00%	23.00%	23.00%	34.00%	34.00%
ZHEJIANG TIANLAN
Research and development costs \| ¥		¥ 23,419,000		¥ 28,589,000		¥ 19,018,000
Shares issued \| shares	82,572,000	82,572,000	82,572,000	82,572,000
Impairment of long-lived assets \| ¥		¥ 0		¥ 2,742,000		¥ 0
ZHEJIANG TIANLAN \| Accounts Receivable
Concentration percentage	10.00%	10.00%
ZHEJIANG TIANLAN \| Revenue
Concentration percentage	35.00%	35.00%	39.00%	39.00%	40.00%	40.00%
ZHEJIANG TIANLAN \| Revenue \| Customer One
Concentration percentage	16.00%	16.00%	16.00%	16.00%	17.00%	17.00%