Fair value measurements (Carrying Values And Fair Values Of Financial Instruments Not Measured At Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	$ 2,460	$ 2,628
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,124	2,731
Short-term debt	0	800
Long-term debt	14,508	14,379
Hybrid debt	419	419
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
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	3,124	2,731
Short-Term Debt, Fair Value		797
Long-term Debt, Fair Value	13,149	12,979
Hybrid debt, Fair Value	476	479
Liabilities, Fair Value Disclosure	16,749	16,986
Portion at Other than Fair Value Measurement \| Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,498	2,680
Assets, Fair Value Disclosure	2,498	2,680
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	0	0
Short-Term Debt, Fair Value		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 \| Total Level 1, Level 2, and Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,498	2,680
Assets, Fair Value Disclosure	2,498	2,680
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,124	2,731
Short-Term Debt, Fair Value		797
Long-term Debt, Fair Value	13,149	12,979
Hybrid debt, Fair Value	476	479
Liabilities, Fair Value Disclosure	16,749	16,986
Reported Value Measurement [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Private debt held-for-investment	2,460	2,628
Assets, Fair Value Disclosure	2,460	2,628
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Repurchase agreements	3,124	2,731
Short-term debt		800
Long-term debt	14,508	14,379
Hybrid debt	419	419
Liabilities, Fair Value Disclosure	$ 18,051	$ 18,329

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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- References

No definition available.

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- References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

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

+ References

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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.

+ References

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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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- Definition

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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- Definition

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.

+ References

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