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Share-Based Compensation - Performance shares and units additional information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Expected volatility	25.10%	24.00%	24.20%
Risk free interest rate	4.10%	2.00%	1.00%
Performance Common Shares and Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Expected volatility	30.40%	38.10%	37.50%
Risk free interest rate	4.60%	1.70%	0.30%
Performance shares and units granted	568,576	690,772	685,104
Weighted average grant date fair value	$ 74.09	$ 49.91	$ 37.38
Aggregate fair value of vested restricted share and unit awards (in millions)	$ 14	$ 27	$ 24
Aggregate intrinsic value of performance shares outstanding	$ 4
Performance Common Shares and Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	0.00%
Performance Common Shares and Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	200.00%

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Share-Based Compensation Performance Awards Payout Percentage

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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