Employee Benefit Plans (Summary Of Status Of Defined Benefit Plans For U.S. Employees) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	$ 8,882	$ 10,259	$ 6,564
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	7,548	6,944	6,015
Interest cost	7,702	7,052	6,385
U.S. Employees [Member] | Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	138,392	118,166
Service cost	7,548	6,944
Interest cost	7,702	7,052
Actuarial loss	26,802	14,631
Benefits paid	(5,080)	(8,401)
Benefit obligation at end of year	175,364	138,392
Fair value of plan assets at beginning of year	114,470	100,728
Actual return on plan assets	(11,309)	15,383
Actual contributions during the year	3,223	6,760
Fair value of plan assets at end of year	101,304	114,470
Funded status at end of year	$ (74,060)	$ (23,922)