The maximum amount of compensation expense incurred on the reporting period.

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- Definition

Estimated amount of compensation expense excepted to be recorded.

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- Definition

The period of performance for options under LTIP.

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- Definition

Share based compensation reduction Of expense

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- Definition

Description about the Period in which option vested or expired.

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- Definition

Unrecognized compensation expense of reporting period.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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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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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- Definition

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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Stock Compensation Plans - Additional information (Details) - USD ($)	3 Months Ended				6 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	29,661					29,661		35,661
Stock Option Period, Description						All options expire ten years from the date of grant. Vested options of retirees expire on the earlier of the scheduled expiration date or one year after the retirement date.
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition						1 month
Allocated Share-based Compensation Expense	$ 280,000		$ 351,000,000			$ 786,000	$ 908,000
Compensation Expense, Maximum	6,800,000					6,800,000
Estimated Compensation Expense, Excepted	4,500,000					4,500,000
Unrecognized Compensation Expense	1,300,000					1,300,000
Reduction of expense	$ 432,000		$ 825,000			$ 842,000	$ 1,500,000
Executive Long-Term Equity Incentive Plan [Member]
Stock Option Period, Description						The value of awards issued in 2021 and 2022 under the Executive LTIP will be determined individually at the end of each respective 36 month performance period ending December 31. The benefits earned under these LTIPs will be paid out in equity in the first quarter following the end of the performance period. The participants will receive all or a portion of the award if their employment is terminated by the Company without cause, by the participant in certain situations, or by death, disability or retirement of the participant.
Share-based Compensation, Performance Period						3 years
Executive Long-Term Equity Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	20.00%					20.00%
Executive Long-Term Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	50.00%					50.00%
Equity Plan 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000					900,000
Long Term Equity Incentive Plan2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,200,000					1,200,000
Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					86,190	86,190
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	244,834					244,834		161,674
Performance Stock Units (PSUs) [Member] \| Executive Long-Term Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					86,190
Restricted Stock Awards (RSAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						52,713
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	70,713					70,713		58,260
Restricted Stock Awards (RSAs) [Member] \| Key Long-Term Equity Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		19,612
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						33,101
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	31,796					31,796		51,773
Restricted Stock Units (RSUs) [Member] \| Key Long-Term Equity Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				17,542
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						3 years
Restricted Stock Units (RSUs) [Member] \| Key Long-Term Equity Incentive Plan 2015 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	5.00%					5.00%
Restricted Stock Units (RSUs) [Member] \| Key Long-Term Equity Incentive Plan 2015 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%					10.00%
Restricted Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	347,343					347,343
Short Term Incentive Plan [Member]
Allocated Share-based Compensation Expense						$ 2,300,000		$ 2,700,000
Restricted Stock Grants [Member] \| Share-based Compensation Award, Tranche One [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						14,712