Accounts receivable	12 Months Ended
Dec. 31, 2020
Receivables [Abstract]
Accounts receivable	Accounts receivableAccounts receivable are held at their nominal amount less an allowance for expected credit losses. The adoption of ASC 326 on January 1, 2020 did not have a material impact on our third-party accounts receivable balances either on transition or at the year end. In calculating the expected credit losses we assumed that the accounts receivable are performing, mature within three months, and have a Baa3 credit rating. Refer to Note 6 - "Current expected credit losses" for further information.

The entire disclosure for claims held for amounts due a entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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