Goodwill and Other Intangible Assets - Changes in carrying amount of goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in carrying amount of goodwill
Goodwill, beginning balance	$ 367,809	$ 327,425
Goodwill, ending balance	452,007	367,809
Accumulated impairment losses	306,000	306,000	$ 306,000
Gross goodwill	758,000	673,000	$ 633,000
Three Shores
Changes in carrying amount of goodwill
Acquisitions		$ 40,384
FinTrust
Changes in carrying amount of goodwill
Acquisitions	14,163
Aquesta
Changes in carrying amount of goodwill
Acquisitions	$ 70,035

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 before 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 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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