XML 49 R35.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Accounting policies (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Accounting Policies [Abstract] |
Schedule Of Property Plant And Equipment Useful Life [Table Text Block] | Rates are determined based on the estimated useful lives of the assets as follows:
Buildings |  | 5 to 40 years
Plant and equipment |  | 4 to 40 years
Distribution system |  | 3 to 40 years
Office furniture, fixtures and equipment |  | 3 to 10 years
Vehicles |  | 3 to 10 years
Leasehold improvements |  | Shorter of 5 years or lease term
Lab equipment |  | 5 to 10 years
Estimated Fair value Of Reporting Segment [Table Text Block] | The respective weightings the Company applied to each method as of December 31, 2017 were consistent with those used as of December 31, 2016 and were as follows:
Method |  | Retail |  | Bulk |  | Manufacturing |
Discounted cash flow |  |  | 80 | % |  | 80 | % |  | 80 | %
Guideline public company |  |  | 10 | % |  | 10 | % |  | 10 | %
Mergers and acquisitions |  |  | 10 | % |  | 10 | % |  | 10 | %
|  |  | 100 | % |  | 100 | % |  | 100 | %

X
- Definition Tabular disclosure of estimated fair value of reporting segment. + References No definition available. + Details
Name: | cwco_EstimatedFairValueOfReportingSegmentTableTextBlock
Namespace Prefix: | cwco_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure of accounting policy for schedule of property plant and equipment useful life. + References No definition available. + Details
Name: | cwco_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock
Namespace Prefix: | cwco_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration