Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Available-for-sale	$ 12,238,316	$ 14,450,027
Trading securities	43,523	46,235
Equity securities with readily determinable fair values	6,210	7,153
Equtiy Securities without Readily Determinable Fair Values	6,094	2,049
Federal Reserve Bank Stock	34,795	34,379
Federal Home Loan Bank Stock	10,678	10,428
Equity Method Investments	1,434	1,834
Private Equity Investments	178,127	147,406
Total investment securities	$ 12,519,177	$ 14,699,511

Amount of investment in equity securities without readily determinable fair values.

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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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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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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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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).

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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