Balance sheet information - Goodwill Impairment (Details) $ in Thousands	12 Months Ended
Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)
Goodwill [Line Items]
Number of reporting segments \| segment	3	3
Goodwill impairment	$ 0	$ 0	$ 2,666
Advertising
Goodwill [Line Items]
Goodwill impairment		$ 2,600

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration