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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposit Premium, Percentage

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans And Leases Receivable, Percent Of Book Value

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of financial assets (as defined) recognized as of the acquisition date.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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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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Mergers and acquisitions - Atlantic Capital Bank Narrative (Details) $ in Thousands		12 Months Ended
	Apr. 05, 2019 USD ($) branch	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Deposits assumed in acquisition		$ 4,934,938	$ 4,171,717
Goodwill		169,051	137,190	$ 137,190
Merger related expenses		5,385	$ 1,594	$ 19,034
Atlantic Capital Bank
Business Acquisition [Line Items]
Transaction value	$ 36,790
Deposits assumed in acquisition	$ 588,877
Deposit premium percentage	6.25%
Loans, net of fair value adjustments	$ 374,399
Percent of book value for acquired loans	99.32%
Goodwill	$ 31,961
Merger related expenses		$ 4,778
TENNESSEE \| Atlantic Capital Bank
Business Acquisition [Line Items]
Number of branches acquired \| branch	11
GEORGIA \| Atlantic Capital Bank
Business Acquisition [Line Items]
Number of branches acquired \| branch	3