Percentage of option vesting rate.

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Performance Measurement Amount In Assets

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Share based compensation arrangement by share based award number of shares average adjusted earnings per share growth percentage.

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Share based compensation arrangement by share based payment award number of shares issued upon vesting based on core return percentage.

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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- Definition

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

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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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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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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Description of method used to estimate fair value of award under share-based payment arrangement.

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- Definition

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

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

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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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of 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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Stock Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 27, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	6 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit	$ 48.91
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Method Used	Black-Scholes options pricing model
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.76%	1.83%	1.83%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.23%	1.62%	1.62%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years 5 months 1 day	6 years 7 months 20 days	6 years 7 months 20 days
Percentage of Option Vesting Rate	20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate	30.11%	26.69%	26.69%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 12.99	$ 7.31	$ 7.31
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 9,486,000	$ 4,052,000	$ 5,742,000
Share-based Payment Arrangement, Expense	1,316,000	1,377,000	1,489,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 4,456,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,648,000	1,293,000	1,693,000
DIVIDENDS PAYABLE	21,388,000	18,484,000
Other Liabilities [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
DIVIDENDS PAYABLE	$ 52,000	49,000
Two Thousand Twenty One Omnibus Stock and Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	2,207,511			2,500,000
Two Thousand Twenty One Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of Option Vesting Rate	20.00%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance Measurement Amount In Assets	$ 50,000,000,000
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance Measurement Amount In Assets	$ 10,000,000,000
Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	2 years
Percentage of Option Vesting Rate	20.00%
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 3,004,000	$ 2,157,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 5 months 1 day	1 year 8 months 8 days
Restricted Stock Units [Member] \| Officers [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 1,329,000	$ 1,301,000	995,000
Restricted Stock Units [Member] \| Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	600,000	635,000	620,000
Restricted Stock [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, Vested in Period, Fair Value	$ 2,947,000	$ 1,924,000	$ 1,597,000
Performance Shares [Member] \| Executives And Other Officers [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement , Award Requisite Service Period	3 years
Vesting period	3 years
Share Based Compensation, Number of Shares Average Adjusted Earnings Per Share Growth Percentage	50.00%
Performance Shares [Member] \| Maximum [Member] \| Executives And Other Officers [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation, Number Of Shares Issued Upon Vesting Based On Core Return Percentage	200.00%
Performance Shares [Member] \| Minimum [Member] \| Executives And Other Officers [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation, Number Of Shares Issued Upon Vesting Based On Core Return Percentage	0.00%