Fair value measurements (Carrying Values And Fair Values Of Financial Instruments Not Measured At Fair Value) (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	$ 2,261	$ 2,411
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,225	3,324
Short-term debt	668	1,499
Long-term debt	17,990	15,728
Hybrid debt	428	422
Portion at Other than Fair Value Measurement \| Level 1
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	0	0
Assets, Fair Value Disclosure	0	0
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	0	0
Short-Term Debt, Fair Value	0	0
Long-term Debt, Fair Value	0	0
Hybrid debt, Fair Value	0	0
Liabilities, Fair Value Disclosure	0	0
Portion at Other than Fair Value Measurement \| Level 2
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	0	0
Assets, Fair Value Disclosure	0	0
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,225	3,324
Short-Term Debt, Fair Value	657	1,498
Long-term Debt, Fair Value	15,412	14,045
Hybrid debt, Fair Value	467	484
Liabilities, Fair Value Disclosure	19,761	19,351
Portion at Other than Fair Value Measurement \| Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,292	2,445
Assets, Fair Value Disclosure	2,292	2,445
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	0	0
Short-Term Debt, Fair Value	0	0
Long-term Debt, Fair Value	601	576
Hybrid debt, Fair Value	0	0
Liabilities, Fair Value Disclosure	601	576
Portion at Other than Fair Value Measurement \| Total Level 1, Level 2, and Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,292	2,445
Assets, Fair Value Disclosure	2,292	2,445
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,225	3,324
Short-Term Debt, Fair Value	657	1,498
Long-term Debt, Fair Value	16,013	14,621
Hybrid debt, Fair Value	467	484
Liabilities, Fair Value Disclosure	20,362	19,927
Reported Value Measurement [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,261	2,411
Assets, Fair Value Disclosure	2,261	2,411
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,225	3,324
Short-term debt	668	1,499
Long-term debt	17,990	15,728
Hybrid debt	428	422
Liabilities, Fair Value Disclosure	$ 22,311	$ 20,973

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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Fair value of financial and nonfinancial obligations.

+ References

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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