Percentage of option vesting rate.

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Performance Measurement Amount In Assets

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Remaining Percentage of Option Vesting Rate.

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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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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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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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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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The floor 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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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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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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Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Apr. 27, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option vesting rate			20.00%
Remaining percentage of option vesting rate			20.00%
Duration of options granted, years			10 years
Stock options outstanding, exercise price range, lower			$ 7.87
Stock options outstanding, exercise price range, upper			$ 48.91
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan	$ 4,863,000		$ 4,863,000
Weighted-average period of unrecognized compensation cost recognition, years			1 year 11 months 26 days
Total fair value of shares vested			$ 1,246,000	$ 878,000
Stock compensation expense	296,000	$ 344,000	987,000	1,033,000
Dividends Payable	21,380,000	18,476,000	21,380,000	18,476,000		$ 18,484,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance measurement amount in assets		50,000,000,000		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		$ 10,000,000,000
Two Thousand Twenty One Omnibus Stock and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of stock for issuance under the plan	2,207,511		2,207,511		2,500,000
2021 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option vesting rate			20.00%
Other Liabilities [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends Payable	$ 72,000	64,000	$ 72,000	64,000		$ 49,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan	3,556,000	1,872,000	$ 3,556,000	$ 1,872,000
Weighted-average period of unrecognized compensation cost recognition, years			1 year 5 months 26 days	1 year 6 months 3 days
Total fair value of shares vested			$ 883,000	$ 1,114,000
Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	150,000,000	150,000,000	450,000,000	485,000,000
Restricted Stock [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	347,000	419,000	$ 926,000	1,016,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of stock for issuance under the plan					2,500,000
Restricted shares vesting period			2 years
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan	3,556,000	1,872,000	$ 3,556,000	$ 1,872,000
Weighted-average period of unrecognized compensation cost recognition, years			1 year 5 months 26 days	1 year 6 months 3 days
Performance Shares [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	347,000	419,000	$ 926,000	$ 1,016,000
Performance Shares [Member] \| Executives And Other Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting period			3 years
Criteria period			3 years
Average adjusted earnings per share growth percentage			50.00%
Performance Shares [Member] \| Executives And Other Officers [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage			200.00%
Performance Shares [Member] \| Executives And Other Officers [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage			0.00%
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan	3,556,000	1,872,000	$ 3,556,000	$ 1,872,000
Weighted-average period of unrecognized compensation cost recognition, years			1 year 5 months 26 days	1 year 6 months 3 days
Restricted Stock Units [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 347,000	$ 419,000	$ 926,000	$ 1,016,000