Other Intangible Assets, net and Goodwill - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Amortization		$ 65,696	$ 41,656	$ 168,049	$ 138,694
Customer First Now
Finite-Lived Intangible Assets [Line Items]
Asset acquisition, consideration transferred	$ 6,446
Finite-Lived Intangible Assets, Period Increase (Decrease)	$ 6,446
Remaining Weighted - Average Amortization Period (in years)	4 years 8 months 12 days
Databases | Customer First Now
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Period Increase (Decrease)	$ 5,446
Remaining Weighted - Average Amortization Period (in years)	5 years
Computer software | Customer First Now
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Period Increase (Decrease)	$ 1,000
Remaining Weighted - Average Amortization Period (in years)	3 years