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Percentage of earnings deferred into company stock units.

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Sharebased compensation arrangement by share based payment award award shares potentially converted range percentage.

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

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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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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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage of vesting of award under share-based payment arrangement.

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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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Employee Incentive, Deferred Compensation, And Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant									9,800,000
Stock-based compensation									$ 108,217	$ 102,190	$ 100,789
Provision for income tax expense (benefit)	$ 46,232	$ 37,866	$ 35,073	$ 28,517	$ 31,925	$ 40,632	$ 38,225	$ 38,370	147,688	149,152	140,394
Contributions to profit sharing									13,900	13,400	12,800
Deferred Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested options	$ 491,100								$ 491,100
Weighted-average period, compensation cost expected to recognized, in years									2 years 8 months 12 days
Fair value of stock awards vested									$ 151,300
Incentive Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation									156,200	135,500	111,800
Tax benefit related to stock-based compensation									$ 25,900	$ 11,900	$ 4,000
Restricted Stock Units, PRSUs, and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock awards outstanding	20,900,000								20,900,000
Unvested stock awards outstanding	17,900,000								17,900,000
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									5 years
Award performance period									4 years
Performance-based Restricted Stock Units [Member] \| One to Four Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earned award vested									80.00%
Performance-based Restricted Stock Units [Member] \| Fifth Year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earned award vested									20.00%
SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Elective deferrals vested percentage	100.00%								100.00%
Percentage of earnings deferred into company stock units	5.00%								5.00%
Percentage of earnings deferred into company stock units, Additional elective deferral									1.00%
Minimum [Member] \| Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									1 year
Minimum [Member] \| Deferred Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									1 year
Minimum [Member] \| Restricted Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									1 year
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									1 year
Minimum [Member] \| Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares									0.00%
Minimum [Member] \| SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									1 year
Maximum [Member] \| Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									8 years
Maximum [Member] \| Deferred Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									10 years
Maximum [Member] \| Restricted Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									2 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									10 years
Maximum [Member] \| Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares									200.00%
Maximum [Member] \| SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years									10 years