Elective deferrals vested percentage.

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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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Percentage of earnings deferred into company stock units deferred in mutual funds.

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

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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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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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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

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Sum of the carrying amounts as of the balance sheet date of all investments.

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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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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
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant	6,200,000
Stock-based compensation	$ 27,915	$ 30,450
Provision for income tax expense (benefit)	13,507	16,858
Investments, at fair value	133,761		$ 133,563
Deferred compensation liability	6,500		8,600
Contributions to the Profit Sharing Plan	$ 400	1,300
Mutual Funds [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earnings deferred into mutual funds	2.00%
Investments, at fair value	$ 12,000		$ 11,300
Incentive Stock Award Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	31,200	28,900
Tax deficit related to stock-based compensation recognized in additional paid-in-capital		$ 4,200
Incentive Stock Award Plans \| ASU No. 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Provision for income tax expense (benefit)	$ (16,900)
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock units outstanding	19,500,000
Unvested stock units outstanding	16,100,000
Unrecognized compensation expense related to non-vested options	$ 386,500
Weighted-average period, compensation cost expected to recognized, in years	3 years 1 month 6 days
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years	5 years
Total number of stock units outstanding	600,000
Unvested stock units outstanding	600,000
Award performance period	4 years
SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Elective deferrals vested percentage	100.00%
Percentage of earnings deferred into company stock units	4.00%
Percentage of earnings deferred into company stock units, Company match	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
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] \| Incentive Stock Award Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years	8 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years	8 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	8 years