Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Available-for-sale	$ 9,684,760	$ 12,238,316
Trading securities	28,830	43,523
Equity securities with readily determinable fair values	5,723	6,210
Equity Securities without Readily Determinable Fair Value, Amount	6,978	6,094
Federal Reserve Bank Stock	35,166	34,795
Federal Home Loan Bank Stock	10,640	10,678
Equity Method Investments	0	1,434
Private Equity Investments	176,667	178,127
Total investment securities	$ 9,948,764	$ 12,519,177

Private equity investment securities held.

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- Definition

Sum of Available for Sale, Trading and Non-Marketable securities.

+ References

No definition available.

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- Definition

Amount 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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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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