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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 350
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-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482665/350-30-50-1

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
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-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
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Intangible Assets - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	Mar. 20, 2023	Mar. 31, 2024
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Estimated useful life		10 years
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Estimated useful life		5 years 1 month 6 days
Signature Bridge Bank
Finite-Lived Intangible Assets [Line Items]
Core deposit and other intangibles	$ 464
Signature Bridge Bank \| Core Deposits
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years