XML 64 R42.htm IDEA: XBRL DOCUMENT
v3.20.4

Commitments and contingencies (Details) | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($)
Commitments and contingencies |
Provision for contingent losses | $ 0

X
- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyAccrualProvision
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration