Operating Segments and Related Information Operating Segments and Related Information (Details 6) (US Government, USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011		Jun. 30, 2012	Jun. 30, 2011
US Government
Revenue, Major Customer [Line Items]
Revenues	$ 75,758	$ 111,765	[1]	$ 174,262	$ 230,285	[1]

[1] Amounts have been adjusted for the reclassification of certain discontinued operations to continuing operations.