STOCK-BASED COMPENSATION - PERFORMANCE STOCK AWARDS (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Forfeiture Rate Employees	4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Total Unrecognized Compensation Cost	$ 0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Forfeiture Rate Employees	4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Number of Shares, Unvested at beginning of period	309
Number of Shares, Granted	165
Number of Shares, Vested	(60)
Number of Shares, Forfeited	(61)
Number of Shares, Unvested at end of period	353	309
Shares, Unvested, Weighted Average Grant Date Fair Value, beginning of period	$ 43.36
Shares Granted, Weighted Average Grant Date Fair Value	$ 58.12
Shares Vested, Weighted Average Grant Date Fair Value	$ 38.83
Shares Forfeited, Weighted Average Exercise Price	$ 48.82
Shares, Unvested, Weighted Average Grant Date Fair Value, end of period	$ 50.10	$ 43.36
Total Unrecognized Compensation Cost	15.6
Expected to be Recognized over a Weighted Average Period	4 years
Total Fair Value, Vested in period	3.3	3.7	1.4
Performance Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Evaluation Stock-Based Compensation		2 years	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Number of Shares, Unvested at beginning of period	113
Number of Shares, Granted	71
Number of Shares, Vested	(108)
Number of Shares, Forfeited	(10)
Number of Shares, Unvested at end of period	65	113
Shares, Unvested, Weighted Average Grant Date Fair Value, beginning of period	$ 41.09
Shares Granted, Weighted Average Grant Date Fair Value	$ 66.98
Shares Vested, Weighted Average Grant Date Fair Value	$ 41.12
Shares Forfeited, Weighted Average Exercise Price	$ 54.58
Shares, Unvested, Weighted Average Grant Date Fair Value, end of period	$ 66.96	$ 41.09
Total Unrecognized Compensation Cost	2.0
Total Fair Value, Vested in period	$ 6.0	$ 16.8	$ 0.6

Performance Evaluation Stock-Based Compensation

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Forfeiture Rate Employees

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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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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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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 total fair value of equity-based awards 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 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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Weighted average price of options that were either forfeited or expired.

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- Definition

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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