Capital Stock (Tables)

6 Months Ended

Jun. 30, 2015

Capital [Abstract]

Summary of Cash Dividend Activity

A summary of the cash dividend activity for the six months ended June 30, 2015 and 2014 is as follows:

Declaration Date	Record Date	Payment Date	Cash Dividend per Share	Total
Six Months Ended June 30, 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
Six Months Ended June 30, 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

Summary of Share Repurchases

A summary of common stock repurchases for the six months ended June 30, 2015 and 2014 is as follows:

	Six Months Ended   June 30
	2015		2014
Shares repurchased	9.7		22.6
Average price per share	$	145.63	$	92.10
Aggregate cost	$	1,410.6	$	2,077.2
Authorization remaining at the end of each period	$	4,281.0	$	1,613.4

Summary of Stock Option Activity

A summary of stock option activity for the six months ended June 30, 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	1.2		147.18
Exercised	(2.1	)	67.82
Forfeited or expired	(0.1	)	95.22
Outstanding at June 30, 2015	6.3		85.83		4.73	$	490.9
Exercisable at June 30, 2015	3.4		66.52		2.73	$	335.9

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 six months ended June 30, 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		147.10
Vested	(1.7	)	72.31
Forfeited	(0.1	)	96.51
Nonvested at June 30, 2015	2.7		100.45

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

The following weighted-average assumptions were used to estimate the fair values of options granted during the six months ended June 30, 2015 and 2014:

	2015		2014
Risk-free interest rate	1.96	%	2.16	%
Volatility factor	31.00	%	35.00	%
Quarterly dividend yield	0.425	%	0.500	%
Weighted-average expected life (years)	4.00		3.75

Schedule of Weighted-Average Fair Values Determined for the Periods

The following weighted-average fair values were determined for the six months ended June 30, 2015 and 2014:

	2015		2014
Options granted during the period	$	34.01	$	22.37
Restricted stock awards granted during the period	147.10		90.17