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Acquisition (Amortization Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Amortization of Intangible Assets	$ 13,100	$ 5,000	$ 6,100
2021	6,735
2022	5,120
2023	3,006
2024	2,707
Thereafter	4,597
Finite-Lived Intangible Assets, Net	35,200
Quarton
Business Acquisition [Line Items]
Amortization of Intangible Assets	8,900
Scenario, Plan \| Quarton
Business Acquisition [Line Items]
2020	8,908
2021	2,608
2022	1,775
2023	0
2024	0
Thereafter	0
Finite-Lived Intangible Assets, Net	$ 13,291