Goodwill and intangible assets - Narrative (Details)	12 Months Ended
Dec. 31, 2019
Minimum
Goodwill [Line Items]
Increase (decrease) in estimated after tax cash flows (as a percent)	(19.00%)
Increase (decrease) in WACC (as a percent)	15.00%
Maximum
Goodwill [Line Items]
Increase (decrease) in estimated after tax cash flows (as a percent)	(39.00%)
Increase (decrease) in WACC (as a percent)	45.00%

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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