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Debt Securities, Held-To-Maturity, Percent Of Portfolio

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Number of Securities, Unrealized Losses Position

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Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment.

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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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Securities (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
Securities (Narrative) (Details) $ in Millions	Jun. 30, 2025 USD ($) security	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) security	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Number of securities in an unrealized loss position \| security	759		759		767
Total fair value	$ 17,923.5		$ 17,923.5		$ 17,832.2
Debt securities, unrealized losses	195.6		195.6		255.1
Investment security gains (losses)	0.0	$ 0.1	0.0	$ (189.3)
Provision for (release of) credit losses	15.6	7.9	16.8	0.1
Held to maturity securities	21,400.8		21,400.8		22,296.7
Debt securities, held-to-maturity, accumulated unrecognized loss	$ 1,267.3		$ 1,267.3		$ 1,645.1
Percentage of debt securities, held-to-maturity, portfolio	1		1		1
Proceeds from sale of investment securities	$ 0.0	31.2	$ 0.0	2,000.0
Investment security gain (loss), net	$ 0.0	0.1	$ 0.0	(189.3)
Rating of A or higher
Debt and Equity Securities, FV-NI [Line Items]
Percentage of debt securities, held-to-maturity, portfolio	0.95		0.95		0.96
BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	$ 365.7		$ 365.7		$ 312.6
Percentage of debt securities, held-to-maturity, portfolio	0.02		0.02		0.01
NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	$ 604.4		$ 604.4		$ 590.4
Percentage of debt securities, held-to-maturity, portfolio	0.03		0.03		0.03
Government Sponsored Agency
Debt and Equity Securities, FV-NI [Line Items]
Total fair value	$ 10,026.4		$ 10,026.4		$ 9,672.6
Debt securities, unrealized losses	113.1		113.1		132.5
Held to maturity securities	8,443.5		8,443.5		8,635.0
Debt securities, held-to-maturity, accumulated unrecognized loss	853.9		853.9		1,081.3
Investment security gain (loss), net	0.0	0.0	0.0	(23.0)
Government Sponsored Agency \| BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
Government Sponsored Agency \| NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
Sub-Sovereign, Supranational and Non-U.S. Agency Bonds
Debt and Equity Securities, FV-NI [Line Items]
Total fair value	1,005.2		1,005.2		1,602.4
Debt securities, unrealized losses	26.8		26.8		42.2
Held to maturity securities	4,512.8		4,512.8		4,146.9
Debt securities, held-to-maturity, accumulated unrecognized loss	106.9		106.9		171.3
Investment security gain (loss), net	0.0	0.0	0.0	(48.2)
Sub-Sovereign, Supranational and Non-U.S. Agency Bonds \| BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	1.2		1.2		1.1
Sub-Sovereign, Supranational and Non-U.S. Agency Bonds \| NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
U.S. Government
Debt and Equity Securities, FV-NI [Line Items]
Total fair value	5,600.4		5,600.4		5,009.8
Debt securities, unrealized losses	14.3		14.3		22.9
Investment security gain (loss), net	0.0	0.0	0.0	(34.8)
Other Asset-Backed
Debt and Equity Securities, FV-NI [Line Items]
Total fair value	305.4		305.4		440.8
Debt securities, unrealized losses	6.9		6.9		12.9
Held to maturity securities					107.1
Debt securities, held-to-maturity, accumulated unrecognized loss					0.1
Investment security gain (loss), net	0.0	0.1	0.0	(56.5)
Other Asset-Backed \| BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities					0.0
Other Asset-Backed \| NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities					0.0
Corporate Debt
Debt and Equity Securities, FV-NI [Line Items]
Total fair value	42.6		42.6		76.9
Debt securities, unrealized losses	0.5		0.5		1.6
Provision for (release of) credit losses	0.9	0.1	0.7	(0.6)
Allowance for credit losses for AFS securities	0.9		0.9		0.2
Held to maturity securities	297.5		297.5		351.6
Debt securities, held-to-maturity, accumulated unrecognized loss	7.0		7.0		11.0
Investment security gain (loss), net	0.0	$ 0.0	0.0	$ 0.0
Corporate Debt \| BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
Corporate Debt \| NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
Other
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	626.1		626.1		621.7
Debt securities, held-to-maturity, accumulated unrecognized loss	174.2		174.2		172.5
Other \| BBB
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	0.0		0.0		0.0
Other \| NOT RATED
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities	$ 571.4		$ 571.4		$ 571.0