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Share-based Compensation Plans: Performance Condition (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average recognition period	1 year 8 months 12 days
Performance Share Units - Market Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award - Performance Period Used to Estimate Expected Share Payout	3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (usd per share)	$ 77.95	$ 74.48
Performance Share Award, Percentage of Target	16.21%
Target shares, value	$ 0.5
Performance Shares | Performance Share Units - Market Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	110,747	68,474
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 73.31	$ 69.91
Performance Shares, Granted in Period	50,440
Granted (usd per share)	$ 77.95
Performance Shares, Forfeited in Period	(8,167)
Forfeited (usd per share)	$ 73.43
Performance Shares | Performance Share Units - Performance Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	62,654	45,666
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 67.88	$ 66.19
Performance Shares, Granted in Period	21,615
Granted (usd per share)	$ 71.5
Performance Shares, Forfeited in Period	(4,627)
Forfeited (usd per share)	$ 68.03
Performance Shares | Outstanding Performance Share/Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 4.0
Weighted-average recognition period	1 year 9 months 18 days

X

- Definition

The amount of the total payout for an employee service share-based compensation award for other than options that has been accrued at the Balance Sheet date. The total value includes the stock price, dividends and the percentage payout value.

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Share Based Compensation Arrangement By Share Based Payment Award - Performance Period Used to Estimate Expected Share Payout

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The percentage target for payout of equity compensation awards

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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