Stock-Based Compensation Plans (Details) (USD $)	12 Months Ended									1 Months Ended	12 Months Ended			1 Months Ended
	Dec. 31, 2011 Y plan	Dec. 31, 2010 Y	Dec. 31, 2009	Dec. 31, 2011 1994 Plan Y	Dec. 31, 2011 1994 Plan Granted on 3 Feb 2011 Y	Dec. 31, 2011 1994 Plan Granted on 2 Feb 2010 Y	Dec. 31, 2011 1994 Plan Granted on 23 Feb 2009 Y	Dec. 31, 2011 1994 Plan Granted on 4 Feb 2009 Y	Dec. 31, 2011 1995 Plan Granted on 15 Feb 2011 Y	Jan. 31, 2012 Restricted Stock Units anniversary	Dec. 31, 2011 Stock Bonus Plan	Dec. 31, 2010 Stock Bonus Plan	Dec. 31, 2009 Stock Bonus Plan	Jan. 31, 2012 Independent directors Restricted Stock Units
Stock-Based Compensation Plans
Number of stock-based incentive plans	1
Number of stock option plans superseded	2
Stock-Based Compensation
Restricted stock units awarded (in shares)										361,061				8,550
Estimated value of restricted stock units awarded (in dollars per share)										$ 33.23
Award restrictions lapse percentage										25.00%
Award restrictions lapse on first anniversary of award date										1
Award restrictions lapse on second anniversary of award date										2
Award restrictions lapse on third anniversary of award date										3
Black-Scholes option pricing model assumptions for options granted
Number of Options Granted (in shares)	1,392,000				1,362,000	148,000	24,000	29,000	30,000
Risk Free Interest Rate (as a percent)					2.62%	2.93%	2.08%	2.17%	2.92%
Dividend Yield (as a percent)					1.75%	1.62%	2.48%	1.88%	1.76%
Expected Life (in years)					6.2	6.5	6.5	6.5	6.6
Volatility (as a percent)					39.00%	36.00%	30.90%	30.90%	38.00%
Exercise price for options granted, low end of range (in dollars per share)					$ 29.66
Exercise price for options granted, high end of range (in dollars per share)					$ 32.63
Exercise Price (in dollars per share)						$ 24.75	$ 16.10	$ 21.25	$ 29.58
Weighted Average Fair Value (in dollars per share)					$ 10.33	$ 8.46	$ 4.06	$ 5.86	$ 10.49
Non-Qualified Stock Options activity
Outstanding at the beginning of the period (in shares)	1,124,000
Granted (in shares)	1,392,000				1,362,000	148,000	24,000	29,000	30,000
Exercised (in shares)	(9,000)
Forfeited (in shares)	(373,000)
Outstanding at the end of the period (in shares)	2,134,000	1,124,000
Outstanding and expected to vest at the end of the period (in shares)	2,081,000
Exercisable at the end of the period (in shares)	892,000
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 34.19
Granted (in dollars per share)	$ 29.66
Exercised (in dollars per share)	$ 24.87
Forfeited (in dollars per share)	$ 34.88
Outstanding at the end of the period (in dollars per share)	$ 31.15	$ 34.19
Outstanding and expected to vest at end of the period (in dollars per share)	$ 31.21
Exercisable at end of the period (in dollars per share)	$ 33.92
Weighted-Average Remaining Contractual Life
Outstanding at the end of the period (in years)	4.8	2.6
Outstanding and expected to vest at end of the period (in years)	4.7
Exercisable at end of the period (in years)	3.1
Aggregate Intrinsic Value
Outstanding at the end of the period (in dollars)	$ 8,053,000	$ 1,891,000
Outstanding and expected to vest at end of the period (in dollars)	7,804,000
Exercisable at end of the period (in dollars)	2,471,000
Closing price of share (in dollars per share)	$ 33.66
Total intrinsic value of options exercised (in dollars)	100,000	1,400,000	3,000,000
Number of shares, unvested options
Unvested at the beginning of the period (in shares)	180,000
Granted (in shares)	1,392,000				1,362,000	148,000	24,000	29,000	30,000
Vested (in shares)	(325,000)
Forfeiture (in shares)	(5,000)
Unvested at the end of the period (in shares)	1,242,000	180,000
Weighted-Average Grant-Date Fair Value, unvested stock options
Unvested at the beginning of the period (in dollars per share)	$ 7.85
Granted (in dollars per share)	$ 10.33
Vested (in dollars per share)	$ 9.84
Forfeiture (in dollars per share)	$ 9.25
Unvested at the end of the period (in dollars per share)	$ 10.11	$ 7.85
Unrecognized compensation cost
Unrecognized compensation costs related to unvested share-based compensation arrangements (in dollars)				17,700,000
Weighted-average period for recognition of unrecognized stock-based compensation expense (in years)				3.0
Other disclosures
Shares issued and committed to issue (in shares)											12,000	8,000	10,000
Pre-tax compensation charges for continued and discontinued operations	$ 6,133,000	$ 3,338,000	$ 1,746,000								$ 700,000	$ 400,000	$ 500,000
The anniversary year of employment during which shares are issued to the employee under the plan (in years)				4 years							10 years