Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Investment Securities [Abstract]
Available for sale debt securities	$ 14,780,494	$ 14,450,027
Trading debt securities	31,380	46,235
Equity securities with a readily determinable fair value	6,866	7,153
Equtiy Securities without Readily Determinable Fair Values	2,418	2,049
Federal Reserve Bank Stock	34,532	34,379
Federal Home Loan Bank Stock	10,199	10,428
Equity Method Investments	1,434	1,834
Private equity investments	153,411	147,406
Total investment securities	15,020,734	14,699,511
Interest Receivable, Current	$ 41,400	$ 39,500

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

No definition available.

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- Definition

Investment Securities Disclosure

+ References

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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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.

+ References

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-Name Accounting Standards Codification
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-Publisher FASB
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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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-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

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.

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

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