Pension and Other Post-Retirement Benefits - Defined contribution plans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Defined contribution plan expense	$ 18,083	$ 13,262	$ 12,143
Defined Benefit Plan, Benefit Obligation, Business Combination	$ 918	$ 2,393

Amount of increase in benefit obligation of defined benefit plan from business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(8)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsBenefitObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration