Share-Based Payments (Details 4) (Market stock units, USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Market stock units
Market stock units activity
Beginning Balance, Unvested, Shares	606,000
Beginning Balance, Weighted Average Grant Date Fair Value	$ 94.73
Shares, Granted	271,000	[1]
Weighted Average Grant Date Fair Value, Granted	$ 193.45	[1]	$ 134.95
Shares, Vested	(296,000)
Weighted Average Grant Date Fair Value, Vested	$ 85.12
Shares, Forfeited	(31,000)
Weighted Average Grant Date Fair Value, Forfeited	$ 128.39
Ending Balance, Unvested, Shares	550,000		606,000
Ending Balance, Weighted Average Grant Date Fair Value	$ 128.04		$ 94.73

[1] MSUs granted in 2013 include approximately 18,000 and 39,000 MSUs issued in 2013 based upon the attainment of performance criteria set for 2012 and 2011, respectively, in relation to shares granted in those years. The remainder of MSUs granted during 2013 include awards granted in conjunction with our annual awards made in February 2013 and MSUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.