Business Combination, Reduction To Bargain Purchase, Gain Recognized, Amount

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- Definition

Business Combination, Settlement Process Period

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Number Of Branches

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

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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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Business Combinations - Narrative (Details) $ in Millions				3 Months Ended		12 Months Ended
Business Combinations - Narrative (Details) $ in Millions	Mar. 31, 2023 shares	Mar. 20, 2023 USD ($) branch	Mar. 19, 2023 USD ($)	Mar. 31, 2024 USD ($) branch	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Business Acquisition [Line Items]
Number of branches				419
Settlement period				1 year
Bargain purchase gain \| $						$ 2,000
Reduction to bargain purchase gain \| $				$ 121	$ (2,001)
Core Deposits
Business Acquisition [Line Items]
Estimated useful life				10 years
Signature Bridge Bank
Business Acquisition [Line Items]
Bargain purchase gain \| $		$ 2,010	$ 2,010
Restructuring charges \| $		$ 236
Signature Bridge Bank \| Core Deposits
Business Acquisition [Line Items]
Estimated useful life		10 years
Signature Bridge Bank \| FDIC
Business Acquisition [Line Items]
Shares issued (in shares) \| shares	39,032,006
Signature Bridge Bank \| New York
Business Acquisition [Line Items]
Number of branches		29
Signature Bridge Bank \| California
Business Acquisition [Line Items]
Number of branches		7
Signature Bridge Bank \| North Carolina
Business Acquisition [Line Items]
Number of branches		2
Signature Bridge Bank \| Connecticut
Business Acquisition [Line Items]
Number of branches		1
Signature Bridge Bank \| Nevada
Business Acquisition [Line Items]
Number of branches		1