Derivative Instruments and Hedging Activities - Financial instruments (Details) - Derivatives designated as hedging instruments - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative financial instruments
Fair Value Liability	$ (19,407)	$ (8,339)
Interest rate swap agreements
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	250,000	250,000
Interest rate swap agreements \| Other current liabilities
Derivative financial instruments
Fair Value Liability	(5,872)	(2,157)
Interest rate swap agreements \| Other long-term liabilities
Derivative financial instruments
Fair Value Liability	$ (13,535)	$ (6,182)

Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant