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Acquisitions (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended
Acquisitions (Narrative) (Details) - USD ($) $ in Thousands	Feb. 08, 2019	Jan. 14, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Acquisition holdback			$ 4,990	$ 2,500
Goodwill			295,401		$ 297,146
Transaction costs			1,831	580
Barefoot [Member]
Business Acquisition [Line Items]
Date of acquisition		Jan. 14, 2019
Locust [Member]
Business Acquisition [Line Items]
Date of acquisition	Feb. 08, 2019
2019 Acquisitions [Member]
Business Acquisition [Line Items]
Purchase price			53,600
Acquisition holdback			2,000
Goodwill			11,900
Accounts receivable			12,100
Inventory			7,700
Property and equipment			2,300
Net sales of acquiree since acquisition date				18,200
Estimated pre-tax earnings of acquiree since acquisition date				$ 1,900
Customer relationships [Member] \| 2019 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets			$ 23,300
Useful life			9 years
Non-compete agreements [Member] \| 2019 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets			$ 200
Useful life			2 years