AFS securities in loss position at period-end, change in unrealized loss.

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Amortized cost of available for sale debt securities that the Company sold as part of its plan to reposition a portion of its available for sale debt securities portfolio.

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The available for sale debt securities acquired as part of the Company's plan to reposition a portion of its available for sale debt securities portfolio.

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Estimated yield of the available for sale debt securities sold as part of the Company's plan to reposition a portion of its available for sale debt securities portfolio.

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Yield of the available for sale debt securities acquired as part of the Company's plan to reposition a portion of its available for sale debt securities portfolio.

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Equity Securities Sold, Average Price

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Equity Securities Sold, Shares

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Equity Securities without Readily Determinable Fair Value, Shares

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Exchange Offer, Common Shares Received

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Exchange Offer, Conversion Rate of Common Stock. Conversion rate to Visa Class A shares from each share of Visa Class B-2 shares.

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Shares held at time of exchange offer.

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Fair value adjustments on other securities.

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Fair value of securities on impairment watch list.

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The fair value of investment securities pledged for public funds, repurchase agreements, and borrowings

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The number of investments in a single issuer that exceed 10% of stockholder's equity, excluding obligations of various government-sponsored enterprises such as FNMA, FHLB, and FHLMC.

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Loss on Available for Sale debt securities sold as part of the Company's planned AFS portfolio repositioning.

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Other Securities Loss On Sale

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The percent of decrease in the fair value of securities below amortized cost requiring a review for possible impairment.

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No investment in a single issuer exceeds this percentage of stockholder's equity, other than obligations of various government-sponsored enterprises such as FNMA, FHLB, and FHLMC.

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Proceeds from Sale of Equity Securities

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U.S. Treasury inflation protected securities held at fair value

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Amount of realized 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 of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in equity security without readily determinable fair value.

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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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Investment Securities (Narrative) (Details)	3 Months Ended		6 Months Ended
Investment Securities (Narrative) (Details)	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) Rate	May 03, 2024 USD ($) shares	Mar. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items]
Equity Securities without Readily Determinable Fair Value, Amount		$ 65,780,000	$ 9,413,000	$ 65,780,000	$ 9,083,000		$ 6,988,000	$ 6,978,000
Percentage decrease requiring a review for impairment			20.00%
Fair value of securities on impairment watch list			$ 1,100,000,000		1,600,000,000
Debt Securities, Available-for-sale, Unrealized Loss Position			6,462,218,000		8,134,911,000
Unrealized Loss on AFS Debt Securities			796,304,000		994,534,000
AFS securities in loss position at period-end, change in unrealized loss			(198,200,000)
Securities pledged as collateral			$ 6,900,000,000		6,900,000,000
Debt Securities, Available-for-Sale, Planned Sale, Amortized Cost					$ 1,200,000,000
Debt Securities, Available-for-Sale, Planned Sale, Yield \| Rate					2.10%
Loss on Available for Sale debt securities portfolio repositioning					$ 179,100,000
Debt Securities, Available-for-Sale, Planned Sale, Reinvestment					$ 928,800,000
Debt Securities, Available-for-Sale, Planned Sale, Yield of Reinvestment \| Rate					4.60%
Number of investments in a single issuer that exceed 10% of stockholder's equity			0
No investment in a single issuer exceeds this percentage of stockholder's equity			10.00%
U.S. government and federal agency obligations
Debt Securities, Available-for-sale [Line Items]
U.S. Treasury inflation-protected securities held, at fair value			$ 413,400,000
Debt Securities, Available-for-sale, Unrealized Loss Position			982,542,000		$ 1,846,004,000
Unrealized Loss on AFS Debt Securities			12,749,000		$ 41,859,000
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Losses realized on sales			(4,218,000)	187,543,000
Equity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Equity Securities, FV-NI, Gain (Loss)		$ 178,164,000	1,777,000	$ 178,306,000
Visa Class B-1 Shares
Debt Securities, Available-for-sale [Line Items]
Equity Securities without Readily Determinable Fair Value, Shares \| shares							823,447
Equity Securities without Readily Determinable Fair Value, Carrying Value							$ 0
Exchange Offer, Original Shares Held \| shares							823,447
Visa Class B-2 Shares
Debt Securities, Available-for-sale [Line Items]
Exchange Offer, Common Shares Received \| shares						411,723
Equity Securities without Readily Determinable Fair Value, Amount						$ 0
Visa Class A Shares
Debt Securities, Available-for-sale [Line Items]
Exchange Offer, Conversion Rate of Common Stock						1.5875
Equity Securities Sold, Shares \| shares	218,000	436,000		436,000
Equity Securities Sold, Average Price \| $ / shares	$ 260.56	$ 274.91		$ 274.91
Proceeds from Sale of Equity Securities	$ 56,800,000	$ 119,800,000
Visa Class C Shares
Debt Securities, Available-for-sale [Line Items]
Exchange Offer, Common Shares Received \| shares						163,404
Private Equity Securities
Debt Securities, Available-for-sale [Line Items]
Other Securities, Loss realized on sales			(606,000)
Fair value other securities adjustments, net			$ (4,100,000)