Additional shares registered under the Amended and Restated 2014 Long-Term Incentive Plan.

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The term (in years) when the equity-based award expires as specified in the award agreement.

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No definition available.

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The period (in days) from the vesting date during which the Participant has the right to receive, an amount, in cash and/or shares of the Company's Common Stock as determined by the Committee, equal to the sum of the fair market value of a share of Common Stock on the date such share of Phantom Stock vests and the aggregate amount of cash dividends paid with respect to a share of Common Stock during the period from the grant date of the share of Phantom Stock to the date on which the share vests.

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Face amount or stated value per share of common stock.

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

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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 equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Per share weighted average intrinsic value of equity-based compensation awards forfeited. Excludes stock and unit options.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Purchase price of common stock expressed as a percentage of its fair value.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Long-Term Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 12, 2017	Dec. 31, 2000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of awards	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of shares outstanding at beginning of period	25,136,027
Number of shares granted	4,235,015	4,201,978	4,495,487
Number of shares forfeited	(704,136)
Number of shares expired	(100,727)
Number of shares exercised	(2,360,806)
Number of shares outstanding at end of period	26,205,373	25,136,027
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average exercise price - outstanding at beginning of period	$ 269.69
Weighted average exercise price - granted	383.56	$ 386.44	$ 537.29
Weighted average exercise price - forfeited	434.25
Weighted average exercise price - expired	505.96
Weighted average exercise price - exercised	122.92
Weighted average exercise price - outstanding at end of period	$ 295.98	$ 269.69
Weighted average remaining contractual term (in years) - outstanding	6 years 6 months 9 days
Instrinsic value - outstanding	$ 2,904,974
Number of shares vested and expected to vest	24,667,723
Weighted average execise price - vested and expected to vest	$ 293.65
Weighted average remaining contractual term - vested and expected to vest	6 years 5 months 15 days
Intrinsic value - vested and expected to vest	$ 2,904,723
Number of shares exercisable	16,263,766
Weighted average exercise price - exercisable	$ 223.00
Weighted average remaining contractual term - exercisable	5 years 1 month
Intrinsic value - exercisable	$ 2,894,474
Total intrinsic value - of stock options exercised	$ 735,600	$ 550,400	$ 1,031,600
Exercise Price Equal to Market Price [Abstract]
Number of Options Granted (shares)	4,235,015	4,201,978	4,495,487
Weighted Average Exercise Price (dollars per share)	$ 383.56	$ 386.44	$ 537.29
Weighted Average Fair Value	$ 118.70	$ 126.68	$ 181.65
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected volatility	31.00%	34.00%	35.00%
Expected lives from grant date	5 years 1 month 1 day	5 years 1 month 1 day	5 years 1 month 1 day
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	2.16%	1.84%	1.68%
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Phantom stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period within vesting date that awards may be received	30 days
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of awards	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	100.00%
Non-performance based stock options
Exercise Price Equal to Market Price [Abstract]
Non-cash stock-based compensation expense	$ 492,800	$ 546,000	$ 443,700
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	16,800	14,600	4,800
Unrecognized stock-based compensation cost, net of estimated forfeitures	$ 816,600
Weighted average period for recognition of total unrecognized compensation expense (in years)	1 year 11 months
Restricted stock
Exercise Price Equal to Market Price [Abstract]
Non-cash stock-based compensation expense	$ 14,500	$ 13,900	$ 15,300
Unrecognized stock-based compensation cost, net of estimated forfeitures	$ 34,900
Weighted average period for recognition of total unrecognized compensation expense (in years)	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Number of shares outstanding at beginning of period	546,820
Number of shares granted	63,030
Number of shares vested	(501,590)
Number of shares forfeited	(2,000)
Number of shares outstanding at end of period	106,260	546,820
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted average grant date fair value at beginning of period	$ 141.85
Weighted average grant date fair value - granted	379.60
Weighted average grant date fair value - vested	115.07
Weighted average grant date fair value - forfeited	381.92
Weighted average grant date fair value at end of period	$ 404.72	$ 141.85
Long-Term Incentive Plan 2000
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance					35,397,043
Number of shares available for future grants	0
Long-Term Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future grants	15,768,378
Amended & Restated Long-Term Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance				18,559,431
Additional Shares Registered	12,000,000
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of shares exercised	(2,249,000)	(1,697,000)	(2,457,000)