Goodwill and Other Intangible Assets - Summary of changes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Impairment of goodwill	$ 0	$ 0
Goodwill
Goodwill, Beginning Balance		1,581,085	$ 1,563,942
Goodwill subsequent fair value adjustment from CenterState acquisition			1,327
Goodwill, Ending Balance	$ 1,923,106	1,923,106	1,581,085
CenterState
Goodwill
Additions, Goodwill from acquisition		$ 342,021
SouthState\|Duncan-Williams
Goodwill
Additions, Goodwill from acquisition			$ 15,816

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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