Significant Transactions with Related Parties and Non-Controlling Shareholders of Subsidiaries - Related parties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related party transaction
Interest paid		$ 132	$ 152
Balances with related parties included in:
Accounts receivable-related parties	$ 2,782	3,860
Accounts payable	6,507	20
Amounts due from related parties	889	8,544
Amounts due to related parties	432	7,021
Marketing services
Related party transaction
Expenses	13,249	10,567	9,142
Indirect subsidiaries of CK Hutchison
Related party transaction
Interest paid		132
Guarantee fee on bank borrowing		320	471
Balances with related parties included in:
Accounts receivable-related parties	2,709	2,761
Amounts due from related parties		23
Amounts due to related parties	$ 432	454
Period of repayable on demand and interest-bearing (in months)	1 month
Indirect subsidiaries of CK Hutchison \| Sales
Related party transaction
Sales	$ 8,306	8,486	9,794
Indirect subsidiaries of CK Hutchison \| Marketing services
Related party transaction
Expenses	546	372	741
Indirect subsidiaries of CK Hutchison \| Management services
Related party transaction
Expenses	922	897	874
Equity investees
Related party transaction
Purchases	2,827	1,182	280
Balances with related parties included in:
Accounts receivable-related parties	73	1,099
Accounts payable	6,507	20
Amounts due from related parties	889	893
Amounts due to related parties		6,567
Other deferred income	1,356	1,648
Equity investees \| Research and development services
Related party transaction
Sales	7,832	9,682	8,429
Equity investees \| Marketing services
Related party transaction
Expenses	$ 12,703	10,195	8,401
Equity investees \| Dividend receivable
Balances with related parties included in:
Amounts due from related parties		$ 7,628
Immediate holding company
Related party transaction
Interest paid			$ 152

Amount of guarantee fee on bank loan incurred with related party.

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Amount of other deferred income as of balance sheet date with related parties.

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Period of repayable on demand and interest-bearing, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Amount of interest expense incurred on a debt or other obligation to related party.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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