Business Combinations (Details) - USD ($)	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill	$ 712,677,000	$ 681,349,000	$ 681,358,000	$ 664,922,000
Measurement period adjustments	400,000	$ (6,669,000)	$ (6,669,000)
2020 Acquisition
Business Acquisition [Line Items]
Gross Aggregate Consideration	78,200,000
Cash Assumed	1,700,000
Business Combination, Consideration Transferred	71,500,000
Business Combination indemnity holdback liability	5,000,000.0
Current Assets	45,900,000
Property, Plant, and Equipment	4,900,000
Goodwill	31,300,000
Other Intangibles	17,600,000
Current Liabilities	21,200,000
Deferred Credits and Other Liabilities	300,000
Measurement period adjustments	$ 400,000