Contingencies and commitments (MVASI Patent Litigation) (Details) - Mvasi Patent Litigation, Genentech, Inc. (Genentech) and the City of Hope	Oct. 29, 2019 patent	Mar. 29, 2019 patent	Aug. 31, 2018 patent lawsuit	Oct. 18, 2017 patent	Oct. 06, 2017 patent
Other Commitments [Line Items]
Loss contingency, patents allegedly infringed	6		8	25	24
Number of patents allegedly infringed		14		27	27
Number of lawsuits filed \| lawsuit			2

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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