Short-term and long-term investments	12 Months Ended
Dec. 31, 2019
ZHEJIANG TIANLAN
Short-term and long-term investments	The Group's short-term investments consist of wealth management products and long-term investments consist of minority ownership interests in one (2018: two) limited liability company, generally from private equity arrangements. These investments are carried under the equity method of accounting, with changes in the carrying value reported as realized gains or losses in the consolidated financial statements.

The entire disclosure for investment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-URI http://asc.fasb.org/topic&trid=75115024

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-URI http://asc.fasb.org/topic&trid=2196928

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-URI http://asc.fasb.org/topic&trid=2197064

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-URI http://asc.fasb.org/topic&trid=2196965

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