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Restricted Stock Units [Abstract]

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The target number of shares to be awarded under the plan if performance goals are achieved.

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The number of shares available for grant under the plan for any type of authorized award.

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

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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

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

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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Net number of non-option equity instruments granted to participants.

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

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Stock-Based Compensation - Long Term Incentive Plan (Details) - Long Term Incentive Plan [Member] - USD ($)	12 Months Ended			36 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,100,000			1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Any Award Type	345,012			345,012
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	0		0	0
Restricted Stock Units (RSUs) [Member]
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	87,727	82,464	79,733	87,727	82,464	79,733	82,680
Performance Shares [Abstract]
Share-based Payment Arrangement, Expense	$ 2,000,000	$ 2,000,000	$ 1,800,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 3,500,000			$ 3,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 54.87	$ 59.40	$ 61.17	$ 54.87	$ 59.40	$ 61.17	$ 56.47
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 60.06	$ 59.29	$ 54.22
Restricted Stock Units [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(31,733)	(29,273)	(35,778)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	38,160	33,594	36,018
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 49.16	$ 55.58	$ 65.29
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(1,164)	(1,590)	(3,187)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 46.82	$ 69.71	$ 63.89
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	35,170			35,170
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0			0
Performance Shares [Abstract]
Share-based Payment Arrangement, Expense	$ 1,322,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 0			$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 44.64			$ 44.64
Performance Shares [Member] \| A 2021 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	0			0
Performance Shares [Abstract]
Share-based Payment Arrangement, Expense	$ 0
Performance Shares [Member] \| A 2020 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	0			0
Performance Shares [Abstract]
Share-based Payment Arrangement, Expense	$ 0
Performance Shares [Member] \| A 2019 Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	35,170			35,170
Performance Shares [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	37,430
Share-based Payment Arrangement, Expense	$ 1,322,000			$ 1,322,000
Performance Shares [Member] \| A 2018 Award [Member]
Performance Shares [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted		31,600
Share-based Payment Arrangement, Expense		$ 2,137,000			$ 2,137,000
Performance Shares [Member] \| A 2017 Award [Member]
Performance Shares [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			41,537
Share-based Payment Arrangement, Expense			$ 572,000			$ 1,971,000
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	70,340			70,340
Maximum [Member] \| Performance Shares [Member] \| A 2021 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	0			0
Maximum [Member] \| Performance Shares [Member] \| A 2020 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	0			0
Maximum [Member] \| Performance Shares [Member] \| A 2019 Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	70,340			70,340
Target Achieved [Member] \| Performance Shares [Member] \| A 2021 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	56,335			56,335
Target Achieved [Member] \| Performance Shares [Member] \| A 2020 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	31,830			31,830