Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Investment Securities [Abstract]
Available for sale debt securities	$ 11,228,616	$ 12,238,316
Trading debt securities	41,584	43,523
Equity securities with a readily determinable fair value	6,083	6,210
Equtiy Securities without Readily Determinable Fair Values	6,445	6,094
Federal Reserve Bank Stock	34,887	34,795
Federal Home Loan Bank Stock	70,112	10,678
Equity Method Investments	0	1,434
Private equity investments	163,418	178,127
Total investment securities	11,551,145	12,519,177
Interest Receivable, Current	$ 32,700	$ 38,800

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

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- Definition

Investment Securities Disclosure

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No definition available.

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- Definition

Private equity investment securities held.

+ References

No definition available.

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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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- 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).

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Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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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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