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Percentage of earnings deferred into company stock units.

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Percentage of earnings deferred into company stock units additional elective deferral.

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Percentage of earnings deferred into company stock units company match.

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

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 equity instruments other than options outstanding, including both vested and non-vested instruments.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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

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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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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	1 Months Ended	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant										5,200,000
Stock-based compensation										$ 100,789	$ 140,461	$ 186,303
Tax benefit related to stock-based compensation										4,000
Provision for income tax expense (benefit)		$ 41,869	$ 36,672	$ 31,060	$ 30,793	$ 1,168	$ 41,603	$ 30,387	$ 13,507	$ 140,394	86,665	61,062
Restricted stock units, charges at the date of modification											55,900
Vesting of outstanding debenture awards	$ 51,400
Options granted during the period										0
Contributions to the Profit Sharing Plan										$ 12,800	7,100	6,500
Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation										$ 111,800	246,700	190,100
Incentive Stock Award Plans [Member] \| ASU No. 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Provision for income tax expense (benefit)											$ (64,700)	4,900
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, charges at the date of modification												$ 58,600
Restricted Stock Units and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock awards outstanding		16,400,000								16,400,000
Unvested stock awards outstanding	13,938,000	14,117,000				13,938,000				14,117,000	13,938,000
Unrecognized compensation expense related to non-vested options		$ 297,400								$ 297,400
Weighted-average period, compensation cost expected to recognized, in years										2 years 9 months 18 days
Fair value of stock awards vested										$ 83,600
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
Total number of stock awards outstanding		700,000								700,000
Unvested stock awards outstanding		700,000								700,000
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, Company match		25.00%								25.00%
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] \| Incentive Stock Award Plans [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] \| Restricted Stock Awards [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] \| Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years										10 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] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years										5 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