Common Equity (Tables)

6 Months Ended

Jun. 30, 2015

Common Equity (Tables) [Abstract]

Shares Repurchased [Table Text Block]

	Six Months Ended June 30
	2015			2014
	Shares	Cost		Shares	Cost
	(In Millions)
Under share repurchase program	—	$	—	0.4	$	18.6
To fulfill exercised stock options and restricted stock awards	0.6	32.0		0.9	38.7
Total	0.6	$	32.0	1.3	$	57.3

Assumptions for valuing options using binomial option pricing model

	2015			2014
Non-qualified stock options granted year to date	516,475			899,500
Estimated fair value per non-qualified stock option	$	5.29		$	4.18
Assumptions used to value the options using a binomial option pricing model:
Risk-free interest rate	0.1% - 2.1%			0.1% - 3.0%
Dividend yield	3.7		%	3.8		%
Expected volatility	18.0		%	18.0		%
Expected forfeiture rate	2.0		%	2.0		%
Expected life (years)	5.8			5.8

Stock option activity

					Weighted-
					Average
			Weighted-		Remaining	Aggregate
	Number of		Average		Contractual Life	Intrinsic Value
Stock Options	Options		Exercise Price		(Years)	(Millions)
Outstanding as of April 1, 2015	6,927,549		$	32.04
Granted	—		$	—
Exercised	(176,619	)	$	21.10
Forfeited	—		$	—
Outstanding as of June 30, 2015	6,750,930		$	32.32
Outstanding as of January 1, 2015	6,770,194		$	29.99
Granted	516,475		$	52.90
Exercised	(535,739	)	$	22.73
Forfeited	—		$	—
Outstanding as of June 30, 2015	6,750,930		$	32.32	5.7	$	85.4
Exercisable as of June 30, 2015	4,014,465		$	26.06	4.0	$	75.9

Non-vested options

			Weighted-Average
Non-Vested Stock Options	Number of Options		Fair Value
Non-vested as of April 1, 2015	2,736,465		$	4.03
Granted	—		$	—
Vested	—		$	—
Forfeited	—		$	—
Non-vested as of June 30, 2015	2,736,465		$	4.03
Non-vested as of January 1, 2015	2,879,855		$	3.65
Granted	516,475		$	5.29
Vested	(659,865	)	$	3.34
Forfeited	—		$	—
Non-vested as of June 30, 2015	2,736,465		$	4.03

Restricted stock activity

			Weighted-Average
Restricted Shares	Number of Shares		Grant Date Fair Value
Outstanding as of April 1, 2015	147,214
Granted	—		$	—
Released	—		$	—
Forfeited	—		$	—
Outstanding as of June 30, 2015	147,214
Outstanding as of January 1, 2015	155,479
Granted	60,164		$	53.83
Released	(68,429	)	$	36.95
Forfeited	—		$	—
Outstanding as of June 30, 2015	147,214

Dividends Declared [Table Text Block]

During the quarter ended June 30, 2015, our Board of Directors declared common stock dividends which are summarized below:

Date Declared	Date Payable	Per Share	Period
April 16, 2015	June 1, 2015	$0.4225	Second Quarter
June 12, 2015	July 6, 2015	$0.2067	45 days through June 28, 2015
June 12, 2015	September 1, 2015	$0.2337	47 days through Aug. 14, 2015