Equity Incentive Compensation Plans (Restricted Stock Units and Performance Share Program) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Restricted Stock Units
Other than stock options activity
Outstanding at the beginning of the period (in shares)	915,022
Granted (in shares)	162,612
Issued (in shares)	(50,660)
Canceled/expired (in shares)	(14,956)
Outstanding at the end of the period (in shares)	1,012,018	[1],[2]
Weighted average grant date fair value
Outstanding at the beginning of the period (in dollars per share)	$ 23.88
Granted (in dollars per share)	$ 50.71
Issued (in dollars per share)	$ 42.94
Canceled/expired (in dollars per share)	$ 40.53
Outstanding at the end of the period (in dollars per share)	$ 27.12
Vest date fair value - issued (in dollars)	$ 2,446
Performance-Based RSUs
Other than stock options activity
Outstanding at the beginning of the period (in shares)	162,849	[3]
Granted (in shares)	59,738
Issued (in shares)	0
Canceled/expired (in shares)	0
Outstanding at the end of the period (in shares)	222,587	[3]
Weighted average grant date fair value
Outstanding at the beginning of the period (in dollars per share)	$ 39.00
Granted (in dollars per share)	$ 63.69
Issued (in dollars per share)	$ 0.00
Canceled/expired (in dollars per share)	$ 0.00
Outstanding at the end of the period (in dollars per share)	$ 45.79
Vest date fair value - issued (in dollars)	$ 0

[1] (1)The balance outstanding includes 43,554 RSUs granted to non-employee directors that are 100% vested at date of grant, but are subject to deferral elections delaying the date on which the corresponding shares are issued.

[2] (2)The balance outstanding includes 469,165 RSUs granted to executive officers and other officers that have vested in accordance with the RSU agreement, but are subject to deferral elections delaying the date on which the corresponding shares are issued.

[3] Reflects the maximum number of performance shares that can be issued.