Pledged and Restricted Assets (Fair Value Of Available For Sale Debt Securities Included In Pledged Assets) (Details) - Collateral that may be repledged or sold - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Financial Instruments Owned and Pledged as Collateral [Line Items]
Debt securities available for sale	$ 44,600.0	$ 43,200.0
SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE
Financial Instruments Owned and Pledged as Collateral [Line Items]
Debt securities available for sale	365.0	464.7
DERIVATIVE CONTRACTS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Debt securities available for sale	$ 69.4	$ 34.7

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

Name:	us-gaap_FinancialInstrumentsOwnedAtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant