Finance lease - Additional Information (Details) - CMBFL Shandong $ in Millions	Jun. 25, 2021 USD ($) subsidiary
Number of subsidiaries \| subsidiary	2
Gross proceeds	$ 49.0
Transaction fees	$ 1.0

The historical cost of the asset(s) sold in connection with the sale of the property to another party and the lease of the property back to the seller.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 840
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481266/840-40-55-50

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 840
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-Section 55
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-URI https://asc.fasb.org/1943274/2147481266/840-40-55-52

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 840
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 51
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481266/840-40-55-51

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479741/842-40-50-2

Name:	us-gaap_SaleLeasebackTransactionHistoricalCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant