Capital Stock (Tables)

12 Months Ended

Dec. 31, 2015

Capital [Abstract]

Summary of Stock Option Activity

A summary of stock option activity for the year ended December 31, 2015 is as follows:

	Number of Shares		Weighted-Average Option Price per Share		Weighted-Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding at January 1, 2015	7.3		$	70.30
Granted	1.3		146.73
Exercised	(2.4	)	67.74
Forfeited or expired	(0.2	)	102.14
Outstanding at December 31, 2015	6.0		87.23		4.21	$	322.7
Exercisable at December 31, 2015	3.9		71.96		2.76	$	263.3

Summary of Nonvested Restricted Stock Activity Including Restricted Stock Units

A summary of the status of nonvested restricted stock activity, including restricted stock units, for the year ended December 31, 2015 is as follows:

	Restricted Stock Shares and Units		Weighted-Average Grant Date Fair Value per Share
Nonvested at January 1, 2015	3.6		$	75.63
Granted	0.9		147.00
Vested	(1.7	)	72.25
Forfeited	(0.1	)	101.57
Nonvested at December 31, 2015	2.7		101.66

Summary of Weighted-Average Assumptions Used to Estimate the Fair Values of Options Granted During the Periods

The following weighted-average assumptions were used to estimate the fair values of options granted during the years ended December 31:

	2015		2014		2013
Risk-free interest rate	1.96	%	2.16	%	1.25	%
Volatility factor	31.00	%	35.00	%	35.00	%
Dividend yield (annual)	1.70	%	2.00	%	2.40	%
Weighted-average expected life (years)	4.00		3.75		4.00

Schedule of Weighted-Average Fair Values Determined For the Periods

The following weighted-average fair values were determined for the years ending December 31:

	2015		2014		2013
Options granted during the year	$	33.97	$	22.41	$	14.64
Restricted stock and stock awards granted during the year	147.00		90.53		63.06

Summary of Cash Dividend Activity

A summary of the cash dividend activity for the years ended December 31, 2015 and 2014 is as follows:

Declaration Date	Record Date	Payment Date	Cash Dividend per Share		Total
Year ended December 31, 2015
January 27, 2015	March 10, 2015	March 25, 2015	$	0.6250	$	166.6
April 28, 2015	June 10, 2015	June 25, 2015	0.6250		163.9
July 28, 2015	September 10, 2015	September 25, 2015	0.6250		163.0
October 27, 2015	December 4, 2015	December 21, 2015	0.6250		163.1
Year ended December 31, 2014
January 28, 2014	March 10, 2014	March 25, 2014	$	0.4375	$	123.4
April 29, 2014	June 10, 2014	June 25, 2014	0.4375		120.5
July 29, 2014	September 10, 2014	September 25, 2014	0.4375		119.2
October 28, 2014	December 5, 2014	December 22, 2014	0.4375		117.6

Summary of Share Repurchases

A summary of common stock repurchases for the years ended December 31, 2015 and 2014 is as follows:

	Years Ended December 31
	2015		2014
Shares repurchased	10.4		30.4
Average price per share	$	145.50	$	98.52
Aggregate cost	$	1,515.8	$	2,998.8
Authorization remaining at the end of each period	$	4,175.9	$	5,691.7