Commitments and contingencies Textual (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Cash Reserve Deposit Required and Made	$ 0.0	$ 0.0
Minimum [Member]
Lessee, Operating Lease, Renewal Term	1 year
Maximum [Member]
Lessee, Operating Lease, Renewal Term	10 years

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant