Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accounts Payable and Accrued Expenses
Accrued research payables	$ 67,149	$ 51,275
Accrued compensation and benefits	20,136	37,911
Accrued costs for potential class action lawsuit settlement	18,000
Accrued costs for potential SEC settlement	12,000
Accrued rent	13,864	14,821
Trade payables	17,372	20,820
Deferred revenue	13,861	8,057
Deferred compensation	2,030	2,525
Accrued restructuring	1,276	6
Accrued transaction processing	4,027	3,257
Other	28,478	27,823
Total	$ 198,193	$ 166,495