Represents the number of stock grants made during the period on the basis of service and performance criteria other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

No definition available.

Share-Based Compensation Plans (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended									0 Months Ended	12 Months Ended	0 Months Ended	12 Months Ended	0 Months Ended	12 Months Ended		0 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Restricted stock and RSUs	Dec. 31, 2012 Restricted stock 2010 and 2011 grant	Dec. 31, 2012 Stock options Y	Dec. 31, 2011 Stock options Y	Dec. 31, 2010 Stock options Y	Dec. 31, 2012 Stock options Non-employee director	Aug. 08, 2011 Restricted stock, 2011 grant	Dec. 31, 2011 Restricted stock, 2011 grant	Mar. 16, 2012 Restricted stock, 2012 grant	Dec. 31, 2012 Restricted stock, 2012 grant item	Feb. 26, 2013 Restricted stock, 2013 grant	Dec. 31, 2012 Restricted stock, 2013 grant item	Dec. 31, 2012 Options with ten-year term	May 16, 2012 Directors Equity Plan Restricted stock Y	May 18, 2011 Directors Equity Plan Restricted stock Y	Jul. 26, 2010 Restricted stock, 2010 grant	Dec. 31, 2010 Restricted stock, 2010 grant
Share-Based Compensation Plans
Shares authorized for future grant	3,181,161
Number of shares
Outstanding at the beginning of the period (in shares)						4,515,560	3,880,052	3,809,229
Granted (in shares)							1,037,250	1,039,400
Exercised (in shares)						(1,018,010)	(266,392)	(827,452)
Expired or forfeited (in shares)						(92,050)	(135,350)	(141,125)
Outstanding at the end of the period (in shares)						3,405,500	4,515,560	3,880,052	186,000							207,180
Exercisable at the end of the period (in shares)						2,028,387
Weighted Average Exercise Price
Outstanding at the beginning of the period, Weighted Average Exercise Price (in dollars per share)						$ 47.39	$ 44.76	$ 41.22
Granted, Weighted Average Exercise Price (in dollars per share)							$ 55.73	$ 42.89
Exercised, Weighted Average Exercise Price (in dollars per share)						$ 41.40	$ 41.60	$ 25.68
Expired or forfeited, Weighted Average Exercise Price (in dollars per share)						$ 49.55	$ 47.57	$ 47.10
Outstanding at the end of the period, Weighted Average Exercise Price (in dollars per share)						$ 49.12	$ 47.39	$ 44.76
Exercisable at the end of the period, Weighted Average Exercise Price (in dollars per share)						$ 49.67
Weighted Average Remaining Contractual Term (In years)
Weighted Average Remaining Contractual Term, stock options outstanding (in years)						3.6
Weighted Average Remaining Contractual Term, stock options exercisable (in years)						3.0
Aggregate Intrinsic Value (In millions)
Aggregate Intrinsic Value, options outstanding						$ 44.4
Aggregate Intrinsic Value, options exercisable						25.4
Vesting period (in years)					5 years	4 years			1 year
Award expiration (in years)						P7Y										P10Y
Weighted average assumptions:
Exercise price (in dollars per share)							$ 55.73	$ 42.89
Risk free interest rate (as a percent)							2.20%	2.35%
Expected life in years							4.8	4.8
Expected volatility (as a percent)							60.00%	60.00%
Expected dividend yield (as a percent)							0.86%	0.93%
Grant date fair value (in dollars per share)							$ 26.98	$ 20.62
Changes in non-vested stock options
Non-vested at the beginning of the period (in shares)						2,369,525
Forfeited (in shares)						(64,425)
Vested (in shares)						(927,987)
Non-vested at the end of the period (in shares)						1,377,113	2,369,525
Weighted Average Grant Date Fair Value
Non-vested options at the beginning of the period (in dollars per share)						$ 22.28
Forfeited (in dollars per shares)						$ 22.29
Vested (in dollars per shares)						$ 20.90
Non-vested options at the end of the period (in dollars per shares)						$ 23.21	$ 22.28
Restricted Shares
Restricted stock granted (in shares)				407,892						86,000		391,050		324,780			16,842	16,079	61,000
The number of grants made during the period on the basis service and performance criteria other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).												138,700		134,725
Fair value of restricted stock granted (in dollars per share)				$ 57.11							$ 37.29	$ 57.42		$ 65.73			$ 49.87	$ 52.24		$ 41.24
Share of common stock													1		1
Period of restriction for trading of shares automatically granted to directors (in years)																	1	1
Number of shares unvested and outstanding				496,450	105,400
Changes in non-vested restricted stock grants and RSUs
Non-vested at the beginning of the period (in shares)				134,800
Granted (in shares)				407,892						86,000		391,050		324,780			16,842	16,079	61,000
Vested (in shares)				(46,242)
Non-vested at the end of the period (in shares)				496,450	105,400
Weighted Average Grant Date Fair Value
Non-vested at the beginning of the period (in dollars per share)				$ 38.72
Granted (in dollars per shares)				$ 57.11							$ 37.29	$ 57.42		$ 65.73			$ 49.87	$ 52.24		$ 41.24
Vested (in dollars per shares)				$ 42.91
Non-vested at the end of the period (in dollars per shares)				$ 53.44
Additional share-based compensation disclosures
Total unrecognized compensation cost						38.4
Weighted average recognition period for unrecognized compensation cost (in years)						1.53
Total intrinsic value of all options exercised						15.5	3.4	16.6
Proceed from option exercises	42.1	11.1	21.2			42.1	11.1	21.2
Tax benefit realized from option exercises						$ 5.4	$ 1.3	$ 6.3