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Non-Insurance Revenues from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue from External Customer [Line Items]
Deferred non-insurance warranty revenue	$ 4,530	$ 4,694	$ 4,714
Contract with customer, liability, revenue recognized	1,400	1,400
Deferred non-insurance warranty acquisition expense	3,525	3,661	$ 3,671
Amortization of deferred sales commissions	1,200
Capitalized Commission Costs
Revenue from External Customer [Line Items]
Deferred non-insurance warranty acquisition expense	3,500	3,600
Capitalized Administrator Service Costs
Revenue from External Customer [Line Items]
Deferred non-insurance warranty acquisition expense	$ 68	$ 62

X

- Definition

The amount of expense recognized in the current period for the periodic realization of capitalized fees that were paid to salespeople, distributors, brokers, and agents at the time of the conclusion of the sale. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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