Restructuring (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended		27 Months Ended
	Mar. 31, 2012		Mar. 31, 2011		Dec. 31, 2011	Dec. 31, 2010	Mar. 31, 2012
Restructuring [Abstract]
Restructuring charges	$ 14,415	[1]	$ 980	[1]	$ 8,584	$ 2,196	$ 25,195
Headcount reduction, percentage	5.00%

[1] See Note 3 "Restructuring."