19A. Future Minimum rental receivable (Details) - ZHEJIANG JIAHUAN - CNY (¥) ¥ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Within 1 year	¥ 791	¥ 750
After 1 year but within 5 years	0	785
After 5 years	0	0
Total	¥ 791	¥ 1,535

No definition available.

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Namespace Prefix:	CLWT_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Details

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