ACCOUNTING POLICIES - Concentration (Details) - Minimum	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues \| Customer concentration risk
Concentrations
Percentage for concentration of credit risk disclosure	4.00%	4.00%	4.00%
Accounts receivable \| Credit concentration risk
Concentrations
Percentage for concentration of credit risk disclosure	6.00%	6.00%

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.

No definition available.

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