Deposits - Maturities of Interest-Bearing Time Deposits (Details) $ in Millions	Sep. 30, 2026 USD ($)
Maturities of interest bearing time deposits
2027	$ 343,386
2028	857
2029	1,477
2030	484
2031	1,069
After 5 years	727
Total	348,000
U.S.
Maturities of interest bearing time deposits
2027	244,282
2028	840
2029	601
2030	440
2031	731
After 5 years	616
Total	247,510
Non-U.S.
Maturities of interest bearing time deposits
2027	99,104
2028	17
2029	876
2030	44
2031	338
After 5 years	111
Total	$ 100,490

Amount of time deposits maturing after the fifth rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 405
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1

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Amount of time deposits maturing in the next rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the fifth rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the fourth rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the third rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the second rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 405
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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