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The decrease in the number of shares (or other type of equity) from the exercise of share appreciation rights under the plan.

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The period of time a share-based award is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

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For presentations that combine terminations, the number of equity awards other than options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the awards or that expired.

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The highest value of award that can be given to any one employee under the plan per period.

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The number of units exercisable at period end.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding awards other than stock options which are in the customized range of exercise prices.

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No definition available.

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The weighted average exercise price of warrants exercised during the period.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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.

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

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The highest quantity of shares an employee can purchase under the plan per period.

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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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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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Share-Based Awards (Details - Other Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Share Based Compensation Arrangements - Other details
Share based compensation expense	$ 34.4	$ 29.8	$ 26.8
Tax benefit of share-based compensation expense	6.9	3.3	3.6
Tax Benefit Realized from Exercise of Stock Options	6.2	7.0	1.6
Employee Equity Plan [Member]
Employee Equity Plan [Abstract]
Total shares authorized under the plan	8,300,000
Shares remaining for issuance	4,000,000
Share Options and SSARs [Member]
Employee Equity Plan [Abstract]
Total shares authorized under the plan	4,900,000
Vesting period for EEP shares	3 years
Shares remaining for issuance	2,700,000
Contractual term, in years	10 years
Share Options [Member]
Assumptions:
Expected life			6 years
Expected volatility			17.70%
Risk-free interest rate			1.00%
Dividend yield			2.70%
RSUs and PSUs [Member]
Employee Equity Plan [Abstract]
Total shares authorized under the plan	3,400,000
Vesting period for EEP shares	3 years
Shares remaining for issuance	1,300,000
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Roll Forward
Outstanding at January 1, 2014	854,898
Granted	333,358	329,174
Performance based adjustment	39,870
Released	(253,389)
Forfeited	(42,115)
Outstanding at December 31, 2014	932,622	854,898
Share Based Compensation Arrangements - Other details
Weighted average grant date fair value	$ 98.86	$ 89.44
Fair value of units vested	20.6	22.8
Unrecognized share-based compensation expense	32.7
Weighted average period of recognition	1 year 10 months
RSU [Member]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Roll Forward
Granted			294,184
Share Based Compensation Arrangements - Other details
Weighted average grant date fair value			$ 65.33
Fair value of units vested			5.5
SSARs [Member]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Roll Forward
Outstanding at January 1, 2014	1,621,815
Granted	153,797	125,561	356,900
Exercised	(270,392)
Forfeited or expired	(12,294)
Outstanding at December 31, 2014	1,492,926	1,621,815
Exercisable at December 31, 2014	1,147,579
Share Based Compensation Arrangements - Other details
Weighted average grant date fair value	$ 14.62	$ 11.25	$ 7.34
Unrecognized share-based compensation expense	2.0
Weighted average period of recognition	1 year 8 months
Assumptions:
Expected life	6 years	6 years	6 years
Expected volatility	18.10%	18.30%	17.60%
Risk-free interest rate	1.90%	1.00%	1.10%
Dividend yield	2.20%	2.30%	2.80%
Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Roll Forward
Granted				27,655
Exercised	(186)
Outstanding at December 31, 2014	8,667
Share Based Compensation Arrangements - Other details
Weighted average remaining contractual term	2 years
Weighted average exercise price, exercises during period	$ 32.12
Weighted average exercise price	$ 31.54
Awards to eligible senior executives [Member]
Employee Equity Plan [Abstract]
Maximum individual award in unit terms	500,000
Maximum individual award in dollar terms	$ 5.0