Goodwill and Other Intangible Assets (Goodwill & Impairment Analysis) (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 465,697,000		$ 465,697,000
Goodwill impairment		$ 0
Changes in the carrying amount of goodwill	$ 0	$ 0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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