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Significant accounting policies - Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2015
Other equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Other equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Licensed motor vehicles | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Licensed motor vehicles | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	4 years
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- Details

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- Details

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