Business Combinations - Net Assets Acquired (Details) - Signature Bridge Bank $ in Millions	Mar. 20, 2023 USD ($)
Business Acquisition [Line Items]
Net assets acquired as of March 20, 2023 before fair value adjustments	$ 2,973
Fair value adjustments:
Loans	(727)
Core deposit and other intangibles	464
Certificates of deposit	27
Other net assets and liabilities	39
FDIC Equity Appreciation Instrument	(85)
Deferred tax liability	(690)
Bargain purchase gain on Signature Transaction, as initially reported	2,010
Measurement period adjustments, excluding taxes	(134)
Change in deferred tax liability	143
As Initially Reported
Fair value adjustments:
Bargain purchase gain on Signature Transaction, as initially reported	2,001
Measurement Period Adjustments
Fair value adjustments:
Bargain purchase gain on Signature Transaction, as initially reported	$ 2,010