Offsetting assets and liabilities - Assets (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Effect of offsetting of the Company's recognized assets
Gross Amounts of Recognized Assets	$ 2,814
Amounts presented in the Consolidated Balance Sheets	2,814
Cash Collateral Received	2,814
Interest Rate Swap
Effect of offsetting of the Company's recognized assets
Gross Amounts of Recognized Assets	2,814
Amounts presented in the Consolidated Balance Sheets	2,814
Cash Collateral Received	$ 2,814

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=SL51823488-111719

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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