XML 66 R54.htm IDEA: XBRL DOCUMENT v2.4.0.8
Stock Options and Other Share-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Fair market values of stock options and stock appreciation rights granted
The fair market values of stock options and stock appreciation rights granted in 2013, 2012 and 2011 were measured on the date of grant using the Black-Scholes option-pricing model, with the following weighted-average assumptions:
 
Year ended December 31
 
2013

 
 
2012

 
2011

 
Stock Options
 
 
 
 
 
 

Expected term in years1
6.0



6.0


6.2


Volatility2
31.3

%

31.7

%
31.0

%
Risk-free interest rate based on zero coupon U.S. treasury note
1.2

%

1.1

%
2.6

%
Dividend yield
3.3

%

3.2

%
3.6

%
Weighted-average fair value per option granted
$
24.48



$
23.35


$
21.24


1 
Expected term is based on historical exercise and postvesting cancellation data.
2 
Volatility rate is based on historical stock prices over an appropriate period, generally equal to the expected term.
Summary of option activity
A summary of option activity during 2013 is presented below:
 
 
 
 
 
 
 
 
 
 
 
Weighted-

 
Average
 
 
 
 
 
Average

 
Remaining
 
Aggregate

 
Shares

 
Exercise

 
Contractual
 
Intrinsic

 
(Thousands)

 
Price

 
Term (Years)
 
Value

Outstanding at
January 1, 2013
71,895

 
$
81.26

 

 

Granted
13,194

 
$
116.45

 

 

Exercised
(8,377
)
 
$
68.20

 

 

Forfeited
(1,086
)
 
$
93.98

 

 

Outstanding at
December 31, 2013
75,626

 
$
88.44

 
6.12
 
$
2,758

Exercisable at
December 31, 2013
51,797

 
$
78.52

 
5.05
 
$
2,403