Stock-Based Compensation and Other Compensation (Details 3) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restricted Stock And Units RSU
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Nonvested, beginning balance - shares	624,793	263,820	381,878
Granted - shares	274,420	541,890	156,682
Vested - shares	(268,683)	(162,437)	(175,225)
Forfeited - shares	(36,336)	(18,480)	(99,515)
Adjustments - shares	0	0	0
Novested, ending balance - shares	594,194	624,793	263,820
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Novested, beginning balance, weighted average grant date fair value	$ 33.26	$ 28.42	$ 28.87
Granted, weighted average grant date fair value	$ 41.41	$ 34.65	$ 28.34
Vested, weighted average grant date fair value	$ 32.56	$ 30.48	$ 28.58
Forfeited, weighted average grant date fair value	$ 36.33	$ 29.32	$ 29.75
Adjustments, weighted average grant date fair	$ 0	$ 0	$ 0
Novested, weighted average grant date fair value	$ 37.15	$ 33.26	$ 28.42
PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Nonvested, beginning balance - shares	673,428	243,994	170,375
Granted - shares	314,400	291,600	159,250
Vested - shares	(235,189)	(48,925)	0
Forfeited - shares	(49,494)	(14,055)	(65,725)
Adjustments - shares	296,368	200,814	(19,906)
Novested, ending balance - shares	999,513	673,428	243,994
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Novested, beginning balance, weighted average grant date fair value	$ 36.30	$ 36.18	$ 32.33
Granted, weighted average grant date fair value	$ 42.28	$ 46.66	$ 36.16
Vested, weighted average grant date fair value	$ 23.66	$ 39.78	$ 0
Forfeited, weighted average grant date fair value	$ 33.96	$ 42.14	$ 36.26
Adjustments, weighted average grant date fair	$ 26.01	$ 22.65	$ 28.49
Novested, weighted average grant date fair value	$ 34.55	$ 36.30	$ 36.18

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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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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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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Other than shares newly issued, the number of additional shares issued (for example, a stock split) or canceled (for example, to correct a share issuance), during the period under the plan.

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

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Adjustments Weighted Average Grant Date Fair Value

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No definition available.

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