Acquisitions, Goodwill And Other Intangible Assets (Schedule of Business Acquisitions) (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Apr. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Cash consideration, net of cash acquired		$ 103,858	$ 94,713
Goodwill		$ 496,422		$ 454,728
Schaudt
Business Acquisition [Line Items]
Purchase price	$ 29,383
Net tangible assets, excluding pension obligation	564
Total fair value of net assets acquired	13,064
Goodwill	16,319
Ranch Hand
Business Acquisition [Line Items]
Cash consideration, net of cash acquired	56,709
Contingent consideration	3,000
Purchase price	59,709
Net tangible assets, excluding pension obligation	16,872
Total fair value of net assets acquired	50,172
Goodwill	9,537
Customer Relationships | Schaudt
Business Acquisition [Line Items]
Identifiable intangible assets	10,000
Customer Relationships | Ranch Hand
Business Acquisition [Line Items]
Identifiable intangible assets	24,200
Other intangible assets | Schaudt
Business Acquisition [Line Items]
Identifiable intangible assets	2,500
Other intangible assets | Ranch Hand
Business Acquisition [Line Items]
Identifiable intangible assets	$ 9,100