STOCK PLANS (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2011 M	Dec. 31, 2010	Dec. 31, 2009
Stock-Based Compensation Expense
Total stock-based compensation expense	$ 6,610,000	$ 8,213,000	$ 5,432,000
Tax benefit related to stock-based compensation recognized in the period	2,515,000	3,112,000	2,058,000
Total unrecognized stock-based compensation expense related to nonvested stock options, restricted shares and restricted stock units	18,898,000
Weighted average period of recognition of unrecognized stock-based compensation expense (in months)	37
1995 Lincoln Stock Purchase Plan
Stock Plans
Shares authorized to be purchased	800,000
Shares purchased	4,466,000	4,240,000	7,636,000
1995 Lincoln Stock Purchase Plan | Maximum
Stock Plans
Dollar value of shares that each employee has the ability to purchase on the open market, on a commission-free basis annually under the plan	$ 10,000