Restructuring and Excess Facilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Activities in the restructuring accrual
Beginning Balance	$ 2,920	$ 5,332	$ 11,376
provisions	517	2,991	495
Cash payments, net of sublease income	(844)	(5,403)	(6,539)
Ending Balance	2,593	2,920	5,332
Excess Facilities [Member]
Activities in the restructuring accrual
Beginning Balance	2,862	3,117	7,196
provisions	517	3,061
Cash payments, net of sublease income	(786)	(3,316)	(4,079)
Ending Balance	2,593	2,862	3,117
Campus Consolidation [Member]
Activities in the restructuring accrual
Beginning Balance		1,715	3,860
provisions		(2)	101
Cash payments, net of sublease income		(1,713)	(2,246)
Ending Balance	0	0	1,715
U K Closure [Member]
Activities in the restructuring accrual
Beginning Balance		276	320
provisions		(71)	42
Cash payments, net of sublease income		(205)	(86)
Ending Balance	0	0	276
Scopus Facilities [Member]
Activities in the restructuring accrual
Beginning Balance	58	224	0
provisions		3	352
Cash payments, net of sublease income	(58)	(169)	(128)
Ending Balance	$ 0	$ 58	$ 224