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The expense amount recognized during the period related to the Company's employee stock purchase plan.

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No definition available.

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The fair value of the employee's purchase right calculated using the Black-Scholes model.

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No definition available.

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The maximum number of shares originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for purchase under the employee stock purchase plan.

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No definition available.

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The number of shares under the employee stock purchase plan purchased by eligible employees during the period.

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No definition available.

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The percentage of the market price of common stock participating employees are able to purchase company stock.

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No definition available.

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The noncash expense that represents the cost of restricted stock and performance shares distributed to employees as compensation.

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No definition available.

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Description of performance share award terms as to how many shares or portion of an award are no longer contingent on satisfaction of certain performance conditions, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale.

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No definition available.

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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 tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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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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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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- Definition

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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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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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- Definition

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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- Definition

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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No definition available.

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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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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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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 exercisable or convertible options. 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 exercisable options that may 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 exercisable or convertible options. 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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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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No definition available.

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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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No definition available.

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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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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 exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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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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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Weighted average grant-date fair value of options vested.

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No definition available.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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STOCK COMPENSATION PLANS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangements by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value			$ 44.37	$ 32.75
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			6 years	6 years
Summary of Changes in Options Outstanding Under the Stock Incentive Plans [Rollforward]
Shares authorized for issuance under the 2008 and 2000 Stock Incentive Plans			10.3
Shares available for grant under the Company's stock option plans			7.5
Award vesting period (in years)			3 years
Stock Options Vested and Expected to Vest at December 31, 2011
Aggregate intrinsic value, vested and expected to vest options			$ 24.1
Stock Options Exercised, Impact Disclosures
Cash received by the Company	$ 43.9	$ 52.6	37.5
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	13.4	13.6	9.4
Aggregate intrinsic value	$ 34.8	$ 35.5	$ 44.1
Assumptions the Company Used to Develop Fair Value Estimates
Fair value of the employee's purchase right	$ 31.54	$ 23.32	$ 34.43
Risk free interest rate			2.70%	2.10%
Expected volatility			18.90%	19.70%
Fair Values of Options Granted and the Employee's Purchase Right in the Stock Purchase Plan
Stock option plan expense	$ 0.9	$ 0.0	$ 3.5
Restricted Stock and Performance Shares
Restricted stock, vesting increment			one third increments beginning on the first anniversary of the grant
Performance share awards, vesting conditions			Performance share awards are subject to certain earnings per share, revenue and total shareholder return targets
Restricted stock and performance share compensation expense	100.8	104.1	$ 80.1
Unrecognized compensation cost related to nonvested restricted stock and performance share-based compensation arrangements			$ 90.9
Unrecognized compensation cost weighted average expected future recognition period (in years)			1 year 11 months
Employee Stock Purchase Plan Disclosure
Shares of common stock authorized for issuance under the employee stock purchase plan			1.8
The employee stock purchase plan permits employees to purchase shares of common stock at a certain percentage of the market price (in hundredths)			85.00%
Number of shares purchased by eligible employees			0.2
Expense related to the Company's employee stock purchase plan	$ 8.0	$ 5.5	$ 8.0
Employee Stock Purchase Plan [Member]
Assumptions the Company Used to Develop Fair Value Estimates
Risk free interest rate	1.30%	0.50%	2.30%
Expected volatility	20.00%	20.00%	20.00%
Expected dividend yield	0.00%	0.00%	0.00%
Restricted Stock and Performance Shares [Member]
Summary of Nonvested Shares
Nonvested, beginning of period			1.5
Number of options granted			0.7
Number of options vested			(0.8)
Nonvested, end of period			1.3	1.5
Weighted-average grant date fair value, nonvested, beginning of period			$ 121.36
Weighted-average grant date fair value, granted			170.93
Weighted-average grant date fair value, vested			$ 125.02
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			0.1
Weighted-average grant date fair value, nonvested, end of period			$ 140.58	$ 121.36
Employee Stock Purchase Plan Disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value			$ 145.50
Stock Options [Member]
Changes in Options Outstanding Under the Stock Incentive Plans, Additional Disclosures
Number of options outstanding, beginning balance			1.2
Number of options granted			0.1
Number of options exercised			(0.5)
Number of options cancelled			0.0
Number of options outstanding, ending balance			0.8	1.2
Weighted-average exercise price per option, outstanding, beginning balance			$ 86.55
Weighted-average exercise price per option granted			168.49
Weighted-average exercise price per option exercised			79.43
Weighted-average exercise price per option cancelled			112.61
Weighted-average exercise price per option, outstanding, ending balance			$ 100.30	$ 86.55
Weighted-average remaining contractual term of options outstanding (in years)			4 years
Aggregate intrinsic value of options outstanding			$ 24.1
Stock Options Vested and Expected to Vest at December 31, 2011
Number of options vested and expected to vest			0.8
Weighted-average exercise price per option, vested and expected to vest options			$ 100.30
Weighted-average exercise price per exercisable option			$ 87.24
Weighted-average remaining contractual term, vested and expected to vest options (in years)			4 years
Number of options exercisable			0.6
Weighted-average remaining contractual term, exercisable options (in years)			2 years 9 months
Aggregate intrinsic value, exercisable options			$ 24.1