Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 919,914	$ 751,174
Acquisitions	0	145,544
Measurement period adjustment - First Miami	1,340
Goodwill, ending balance	921,253	896,718
Accumulated impairment losses on goodwill	306,000	306,000	$ 306,000	$ 306,000
First Miami Bancorp, Inc
Goodwill [Roll Forward]
Measurement period adjustment - First Miami	1,339	$ 0
Goodwill, ending balance	$ 24,500

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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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of accumulated impairment loss for 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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Amount of increase (decrease) 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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