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Share-Based Compensation - Restricted Stock Narrative (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized period for recognition		3 years
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award fair value	$ 53.5	$ 18.1	$ 3.3
Vesting period	6 years
Units granted	300,000
Market condition 1	15.00%
Market condition 2	25.00%
Market condition 3	35.00%
Expected volatility	31.60%
Risk-free interest rate	2.00%
Dividend yield	0.00%
Weighted average fair value (in dollars per share)	$ 144.70
Total compensation cost not yet recognized period for recognition	4 years
Options available for future grant under the Company's option plans (in shares)	1,800,000
Restricted stock | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	8 years
Restricted stock | Vesting Period 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted	200,000
Restricted stock | Vesting Period 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted	100,000

X

- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Weighted Average Fair Value

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Market Condition 1, Percent

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Market Condition 2, Percent

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Market Condition 3, Percent

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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

+ References

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-Publisher FASB

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-Topic 718

-SubTopic 10

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- Definition

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.

+ References

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-Topic 718

-SubTopic 10

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-Paragraph 2

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