Investment Securities - Narrative (Details)	3 Months Ended
Mar. 31, 2025 USD ($) security	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Investments, Debt and Equity Securities [Abstract]
Equity securities without readily determinable fair value	$ 67,900,000
Upward adjustments of equity securities without readily determinable fair values	0	$ 0
Downward adjustments of equity securities without readily determinable fair values	20,000	0
Impairment of equity securities without readily determinable fair values	0	2,000
Pledged securities	$ 7,000,000,000.0	$ 7,200,000,000	$ 6,900,000,000
Number of securities by a single non-government sponsored issuer exceeding 10% of shareholders' equity \| security	0

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477220/954-210-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478600/954-210-50-2

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

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Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

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

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

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Securities By A Single Non-Government Sponsored Issuer, Exceeding Ten Percent Of Shareholders' Equity

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