Capital Stock Capital Stock (Summary of RSU and PSU Activity) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock Units (RSUs) [Member]
Shares, Nonvested at January 1, 2013	1.5
Shares, Granted	0.8
Shares, Vested	(0.7)
Shares, Cancelled	(0.1)
Shares, Nonvested at December 31, 2013	1.5	1.5
Weighted average grant date fair value, Outstanding at January 1, 2013	$ 52.53
Weighted average grant date fair value, Granted	$ 60.81	$ 50.90
Weighted average grant date fair value, Vested	$ 52.92
Weighted average grant date fair value, Cancelled	$ 54.80
Weighted average grant date fair value, Outstanding at December 31, 2013	$ 56.19	$ 52.53
Performance Stock Units (PSUs) [Member]
Shares, Nonvested at January 1, 2013	0.2
Shares, Granted	0.1
Shares, Nonvested at December 31, 2013	0.3
Weighted average grant date fair value, Outstanding at January 1, 2013	$ 54.78
Weighted average grant date fair value, Granted	$ 64.01
Weighted average grant date fair value, Outstanding at December 31, 2013	$ 58.10