Redeemable non-controlling interest ("NCI") - Changes in Redeemable Non-controlling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 8,446	$ 7,701
Net loss attributable to redeemable non-controlling interest	2,258	394
Adjustment of NCI to redemption value	(1,599)	(1,139)
Ending balance	$ 7,787	$ 8,446

Amount of noncontrolling interests which are redeemable by the parent entity, classified as other equity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (12)(c)
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant