Elective deferrals vested percentage.

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- Definition

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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- Definition

Share based compensation arrangement by share based payment award award restriction period for sale or disposition.

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

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- Definition

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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- Definition

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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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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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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Percentage of vesting of share-based compensation awards.

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Employee Incentive, Deferred Compensation, And Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant			5,300,000
Stock-based compensation			$ 75,382	$ 81,613
Contributions to the Profit Sharing Plan	$ 3,400	$ 1,800	$ 10,100	5,500
Minimum [Member] \| Deferred Compensation Plans [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
Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	31,700	$ 32,500	$ 82,500	$ 98,100
Incentive Stock Award Plans [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Incentive Stock Award Plans [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested options	$ 292,200		$ 292,200
Weighted-average period, compensation cost expected to recognized, in years			2 years 10 months 24 days
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
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	16,600,000		16,600,000
Unvested stock awards outstanding	12,900,000		12,900,000
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock awards outstanding	600,000		600,000
Unvested stock awards outstanding	600,000		600,000
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%
Performance-based Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			0.00%
Performance-based Restricted Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			200.00%
Restricted Stock Award [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period for sale or disposition			1 year
Restricted Stock Award [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period for sale or disposition			5 years
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%
SWAP Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
SWAP Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years