STOCK-BASED COMPENSATION PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 plan	Dec. 31, 2012	Dec. 31, 2011
Stock-based compensation plans
Number of stock-based employee compensation plans	2
Non-cash stock-based compensation expense	$ 7,800,000	$ 4,800,000	$ 3,900,000
Total unrecognized compensation cost related to non-vested stock awards	16,900,000
Weighted average period over which compensation cost is expected to be recognized	1 year 8 months 12 days
Stock option
Stock-based compensation plans
Total intrinsic value of awards exercised	44,600,000	101,800,000	60,900,000
Total amount of cash received from the exercise of options	14,600,000	26,000,000	28,500,000
Tax benefit associated with the exercise of awards	17,900,000	39,800,000	22,400,000
Tax benefit associated with the exercise of awards recorded to paid-in-capital	15,400,000	37,500,000	20,400,000
Total Options
Outstanding at the beginning of the period (in shares)	3,159,542
Granted (in shares)	61,485
Exercised (in shares)	(1,221,632)
Forfeited (in shares)	(112,241)
Outstanding at the end of the period (in shares)	1,887,154	3,159,542
Exercisable at the end of the period (in shares)	576,562
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 18.96
Granted (in dollars per share)	$ 53.45
Exercised (in dollars per share)	$ 11.87
Forfeited (in dollars per share)	$ 28.12
Outstanding at the end of the period (in dollars per share)	$ 24.14	$ 18.96
Exercisable at the end of the period (in dollars per share)	$ 21.92
Weighted Average Remaining Contractual Term (In Years)
Outstanding at the end of the period	5 years 7 months 6 days
Exercisable at the end of the period	5 years 4 months 24 days
Aggregate Intrinsic Value
Outstanding at the end of the period	64,768,000
Exercisable at the end of the period	$ 21,060,000
Weighted average date fair value per share of options granted (in dollars per share)	$ 16.16	$ 10.38	$ 7.23
Stock option | Minimum
Stock-based compensation plans
Vesting period	4 years
Expiration period	7 years
Stock option | Maximum
Stock-based compensation plans
Vesting period	5 years
Expiration period	10 years
2011 Stock Plan
Stock-based compensation plans
Number of shares authorized for issuance	8,500,000
Number of shares reserved for every share granted that are Full Share Awards	1.8
Number of shares available for grant for every share forfeited that are Full Share Awards	1.8
2007 Stock Plan
Stock-based compensation plans
Granted (in shares)	0