Stock Compensation Plans (Details 1) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding - beginning of year, Weighted-average Exercise Price	$ 40.50
Granted, Number of Shares	602,905
Granted, Weighted Average-exercise Price	$ 56.87
Exercised, Number of Shares	(764,001)
Exercised, Weighted-average Exercise Price	$ 21.74
Canceled or expired, Number of Shares	(55,228)
Canceled or expired, Weighted-average Exercise Price	$ 48.16
Outstanding - end of year, Number of Shares	3,168,363	3,384,687
Outstanding - end of year, Weighted Average-axercise Price	$ 33.57
Outstanding - end of year, Weighted-average Remaining Contractual Term	7 years
Outstanding - end of year, Aggregate Intrinsic Value	$ 28.9
Option expected to vest, Number of Shares	3,117,761
Option expected to vest, Weighted-average Exercise Price	$ 33.45
Option expected to vest, Weighted-average Remaining Contractual Term	7 years
Option expected to vest, Aggregate Intrinsic Value	28.8
Options exercisable, Number of Shares	1,734,601
Options exercisable, Weighted-average Exercise Price	$ 28.49
Options exercisable, Weighted-average Remaining Contractual Term, Exercisable	5 years
Options exercisable, Aggregate Intrinsic Value	$ 24.6

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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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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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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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Weighted average remaining contractual term for fully vested and expected to vest options that are 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 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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Number of share options (or share units) exercised during the current period.

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