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Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Jun. 07, 2020
Goodwill [Line Items]
Goodwill			$ 1,581,085	$ 1,563,942
CSFL
Goodwill [Line Items]
Goodwill			$ 562,400	$ 562,400	$ 562,370
Goodwill related to the CSFL merger		$ 15,800
Goodwill increased	$ 1,300