Incentive Based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2014

Incentive Based Compensation Plans [Abstract]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

During 2014, 2013 and 2012, we granted stock option awards to both officer and non-officer employees. The weighted average grant date fair value of these awards was based on the following weighted average Black-Scholes assumptions:

	2014		2013		2012
Exercise price per share	$34.49		$33.54		$33.52
Expected annual dividend yield	2.3	%	2.1	%	2.2	%
Expected life in years	5.9		6.1		5.5
Expected volatility	38	%	38	%	41	%
Risk-free interest rate	1.8	%	1.6	%	1.2	%
Weighted average grant date fair value of stock option awards granted	$10.50		$10.25		$10.86

Schedule of Share-based Compensation, Stock Options, Activity

The following is a summary of stock option award activity in 2014.

	Number	Weighted Average	Weighted Average Remaining	Average Intrinsic Value
	of Shares	Exercise Price	Contractual Term	(in millions)
Outstanding at beginning of year	18,104,887	$27.27
Granted	1,935,895	$34.49
Exercised	(5,959,647)	$23.43
Canceled	(653,299)	$34.05
Outstanding at end of year	13,427,836	$29.68	5 years	$	39
Exercisable at end of year	10,435,751	$28.39	4 years	$	39
Expected to vest	2,914,069	$34.18	8 years	$	—

Schedule of Nonvested Restricted Stock Units Activity

The following is a summary of restricted stock award activity in 2014.

	Awards		Weighted Average Grant Date Fair Value
Unvested at beginning of year	4,031,888		$31.80
Granted	1,970,880		$34.98
Vested	(1,845,327	)	$30.64
Forfeited	(709,088	)	$32.73
Unvested at end of year	3,448,353		$34.04

Schedule of Performance Units, Valuation [Table Text Block]

The key assumptions used in the Monte Carlo simulation to determine the fair value of stock-based performance units granted in 2014 and 2013 were:

	2014		2013
Valuation date stock price	$28.29		$28.29
Expected annual dividend yield	2.9	%	2.9	%
Expected volatility	26	%	27	%
Risk-free interest rate	0.7	%	0.3	%
Fair value of stock-based performance units outstanding	$25.06		$21.06