Geographic And Segment Reporting (Schedule Of Geographical Segment Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Segment Reporting Information [Line Items]
Revenues	$ 212,196		$ 188,157
Long-lived assets	154,779	[1]	118,012	[1]
United States [Member]
Segment Reporting Information [Line Items]
Revenues	123,971		112,747
Long-lived assets	122,580	[1]	103,637	[1]
Ireland [Member]
Segment Reporting Information [Line Items]
Revenues	39,739		30,964
Long-lived assets	17,506	[1]	263	[1]
Other International [Member]
Segment Reporting Information [Line Items]
Revenues	48,486	[2]	44,446	[2]
Long-lived assets	$ 14,693	[1],[2]	$ 14,112	[1],[2]
Maximum rate of total revenues	10.00%

[1] Includes property and equipment, net and other assets

[2] No single location within Other International accounts for greater than 10% of total revenues