Segment Reporting and Foreign Operations - Long-lived Assets by Geographic Area (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 243,270	$ 234,803	$ 179,140
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	178,130	176,644	134,393
Ireland
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	50,274	48,182	36,008
Other Foreign Countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 14,866	$ 9,977	$ 8,739