Lease obligations (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CNY (¥)
Operating lease cost \| $	$ 243	$ 257
Short-term lease cost \| $	62	64
Total lease cost \| $	$ 305	$ 321
ZHEJIANG TIANLAN
Total lease cost \| ¥			¥ 7,081
Amortization of right-of-use assets \| ¥			5,837
Interest on lease liabilities included under cost of revenue and selling and administrative expenses \| ¥			¥ 1,244

Amount of interest expense on finance lease liability.

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

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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

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