Stock-Based Compensation Plans (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock Options
Stock-Based Compensation Plans
Intrinsic value of options exercised	$ 2,395,000	$ 26,746,000	$ 46,126,000
2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	501,568
Options outstanding intrinsic value	2,669,000
Options exercisable intrinsic value	2,593,000
Options exercisable weighted average contractual life	8 years 1 month 6 days
1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	691,526
Options outstanding intrinsic value	15,424,000
Options exercisable intrinsic value	$ 15,424,000
Options exercisable weighted average contractual life	3 years 1 month 6 days
40.00 - 49.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	88,323
Exercise Price, lower limit (in dollars per share)	$ 40.00
Exercise Price, upper limit (in dollars per share)	$ 49.99
Weighted Average Remaining Contractual Term	3 years 6 months
60.00 - 69.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	41,556
Exercise Price, lower limit (in dollars per share)	$ 60.00
Exercise Price, upper limit (in dollars per share)	$ 69.99
Weighted Average Remaining Contractual Term	1 year 1 month 6 days
70.00 - 79.99 | 2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	53,836
Exercise Price, lower limit (in dollars per share)	$ 70.00
Exercise Price, upper limit (in dollars per share)	$ 79.99
Weighted Average Remaining Contractual Term	6 years 1 month 6 days
70.00 - 79.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	730
Exercise Price, lower limit (in dollars per share)	$ 70.00
Exercise Price, upper limit (in dollars per share)	$ 79.99
Weighted Average Remaining Contractual Term	1 year 6 months
80.00 - 89.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	104,013
Exercise Price, lower limit (in dollars per share)	$ 80.00
Exercise Price, upper limit (in dollars per share)	$ 89.99
Weighted Average Remaining Contractual Term	4 years 1 month 6 days
90.00 - 99.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	174,323
Exercise Price, lower limit (in dollars per share)	$ 90.00
Exercise Price, upper limit (in dollars per share)	$ 99.99
Weighted Average Remaining Contractual Term	2 years 1 month 6 days
110.00 - 119.99 | 2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	124,414
Exercise Price, lower limit (in dollars per share)	$ 110.00
Exercise Price, upper limit (in dollars per share)	$ 119.99
Weighted Average Remaining Contractual Term	7 years 1 month 6 days
140.00 - 149.99 | 2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	1,499
Exercise Price, lower limit (in dollars per share)	$ 140.00
Exercise Price, upper limit (in dollars per share)	$ 149.99
Weighted Average Remaining Contractual Term	8 years 6 months
140.00 - 149.99 | 1994 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	282,581
Exercise Price, lower limit (in dollars per share)	$ 140.00
Exercise Price, upper limit (in dollars per share)	$ 149.99
Weighted Average Remaining Contractual Term	3 years 1 month 6 days
130.00 - 139.99 | 2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	246,760
Exercise Price, lower limit (in dollars per share)	$ 130.00
Exercise Price, upper limit (in dollars per share)	$ 139.99
Weighted Average Remaining Contractual Term	8 years 7 months 6 days
120.00 - 129.99 | 2009 Plan
Stock-Based Compensation Plans
Number of Options (in shares)	75,059
Exercise Price, lower limit (in dollars per share)	$ 120.00
Exercise Price, upper limit (in dollars per share)	$ 129.99
Weighted Average Remaining Contractual Term	9 years 2 months 12 days