Stock Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Accrual Adjustments

	2014		2013		2012
	Millions
Compensation Cost included in Operation and Maintenance Expense	$	32	$	32	$	25
Income Tax Benefit Recognized in Consolidated Statement of Operations	$	13	$	13	$	10

Stock Options Activity

Changes in stock options for 2014 are summarized as follows:

	Options	Weighted Average Exercise Price		Weighted Average Remaining Years Contractual Term	Aggregate Intrinsic Value
Outstanding as of January 1, 2014	2,615,166	$	34.43
Exercised	519,250	$	30.51
Canceled/Forfeited	20,066	$	39.88
Outstanding as of December 31, 2014	2,075,850	$	35.35	3.8	$	15,016,886
Exercisable at December 31, 2014	2,075,850	$	35.35	3.8	$	15,016,886

Activity For Options Exercised

Activity for options exercised for the years ended December 31, 2014, 2013 and 2012 is shown below:

	2014		2013		2012
	Millions
Total Intrinsic Value of Options Exercised	$	4	$	1	$	4
Cash Received from Options Exercised	$	16	$	7	$	7
Tax Benefit Realized from Options Exercised	$	—	$	—	$	1

Restricted Stock Activity

Changes in restricted stock for the year ended December 31, 2014 are summarized as follows:

	Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years Contractual Term	Aggregate Intrinsic Value
Non-vested as of January 1, 2014	8,800	$	30.18
Vested	8,800	$	30.18
Non-vested as of December 31, 2014	—	$	—	0	$	—

Restricted Stock Units Activity

Changes in restricted stock units for the year ended December 31, 2014 are summarized as follows:

	Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years Contractual Term	Aggregate Intrinsic Value
Non-vested as of January 1, 2014	1,047,569	$	31.30
Granted	356,240	$	35.16
Vested	325,504	$	31.57
Canceled/Forfeited	9,276	$	33.95
Non-vested as of December 31, 2014	1,069,029	$	32.49	1.1	$	44,268,491

Performance Units Information

Changes in performance share units for the year ended December 31, 2014 are summarized as follows:

	Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years Contractual Term	Aggregate Intrinsic Value
Non-vested as of January 1, 2014	802,118	$	33.25
Granted	358,265	$	38.94
Vested	382,504	$	31.25
Canceled/Forfeited	12,246	$	36.45
Non-vested as of December 31, 2014	765,633	$	36.86	1.5	$	31,704,863