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.

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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Goodwill - Changes in carrying amount of goodwill (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill impairment		¥ (22,786)
Tianbo Business
Goodwill [Line Items]
Beginning balance		22,786
Goodwill impairment		¥ (22,786)
Ending balance			¥ 22,786