Financial instruments (Details) - Recurring fair value measurement [member] - USD ($)
$ in Millions |
Jun. 30, 2020 |
Dec. 31, 2019 |
| Marketable securities, time deposits and derivative financial instruments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
$ 193
|
$ 163
|
| Marketable securities, time deposits and derivative financial instruments [member] | Debt securities |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
24
|
24
|
| Marketable securities, time deposits and derivative financial instruments [member] | Fund investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
33
|
37
|
| Marketable securities, time deposits and derivative financial instruments [member] | Total available-for-sale marketable securities [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
57
|
61
|
| Marketable securities, time deposits and derivative financial instruments [member] | Derivative financial instruments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
136
|
102
|
| Associated companies at fair value through profit and loss [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
175
|
186
|
| Long term financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
2,122
|
2,189
|
| Long term financial investments [member] | Fund investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
235
|
233
|
| Long term financial investments [member] | Available-for-sale financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
1,443
|
1,557
|
| Long term financial investments [member] | Contingent consideration receivables [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
444
|
399
|
| Level 1 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
33
|
37
|
| Level 1 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] | Fund investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
33
|
37
|
| Level 1 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] | Total available-for-sale marketable securities [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
33
|
37
|
| Level 1 of fair value hierarchy [member] | Long term financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
904
|
976
|
| Level 1 of fair value hierarchy [member] | Long term financial investments [member] | Available-for-sale financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
904
|
976
|
| Level 2 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
160
|
126
|
| Level 2 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] | Debt securities |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
24
|
24
|
| Level 2 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] | Total available-for-sale marketable securities [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
24
|
24
|
| Level 2 of fair value hierarchy [member] | Marketable securities, time deposits and derivative financial instruments [member] | Derivative financial instruments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
136
|
102
|
| Level 3 of fair value hierarchy [member] | Associated companies at fair value through profit and loss [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
175
|
186
|
| Level 3 of fair value hierarchy [member] | Long term financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
1,218
|
1,213
|
| Level 3 of fair value hierarchy [member] | Long term financial investments [member] | Fund investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
235
|
233
|
| Level 3 of fair value hierarchy [member] | Long term financial investments [member] | Available-for-sale financial investments [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
539
|
581
|
| Level 3 of fair value hierarchy [member] | Long term financial investments [member] | Contingent consideration receivables [member] |
|
|
| Disclosure of fair value measurement of assets [line items] |
|
|
| Financial assets, at fair value |
$ 444
|
$ 399
|