Lease obligations (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 CNY (¥)
Operating lease cost \| $	$ 76		$ 175
Short-term lease cost \| $	220		121
Total finance lease cost \| $	$ 296		$ 296
ZHEJIANG TIANLAN
Interest on lease liabilities included under cost of revenue and selling and administrative expenses \| ¥		¥ 0		¥ 0
Amortization of right-of-use assets \| ¥		0		0
Total finance lease cost \| ¥		¥ 0		¥ 0

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-4

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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