Restructuring Liability (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Restructuring activities
Restructuring expense	$ 12,048	$ 696	$ 12,863	$ 1,650
Kendall Restructuring [Member]
Restructuring activities
Liability, beginning of the period	22,051	24,830	23,328	26,313
Cash payments	(3,901)	(3,726)	(11,323)	(11,137)
Cash received from subleases	2,670	2,355	8,000	7,329
Restructuring expense	524	696	1,339	1,650
Liability, end of the period	$ 21,344	$ 24,155	$ 21,344	$ 24,155