Accounts Payable and Accrued Expenses (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts Payable and Accrued Expenses
Accrued research payables	$ 58,728	$ 38,591
Accrued compensation and benefits	35,134	39,762
Trade payables	21,045	22,624
Accrued rent	18,712	10,947
Deferred revenue	13,157	12,177
Accrued restructuring	4,841	12,295
Deferred compensation	4,491	4,650
Accrued transaction processing	3,054	3,359
Other	18,447	20,657
Total	$ 177,609	$ 165,062