Segment Reporting (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Summary of long-lived assets by geography
Total long-lived assets	$ 251,920	$ 262,517
Americas:
United States	222,232	230,884
Total Americas	222,255	230,919
Europe, Middle East and Africa [Member]
Summary of long-lived assets by geography
Long-Lived Assets in Individual Foreign Countries	4,858	4,813
Japan [Member]
Summary of long-lived assets by geography
Long-Lived Assets in Individual Foreign Countries	2,695	3,960
Asia [Member]
Summary of long-lived assets by geography
Long-Lived Assets in Individual Foreign Countries	22,112	22,825
Other Americas [Member]
Summary of long-lived assets by geography
Long-Lived Assets in Individual Foreign Countries	$ 23	$ 35