Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Aug. 31, 2013 Investment in debt securities [Member]
Operating Leased Assets [Line Items]
Operating leases expenses	$ 2,323,000	$ 1,338,000	$ 1,046,000
Period in which office lease expires	Jan. 01, 2014
New lease agreement term	16 years
New lease agreement date	2013-08
Lease incentives received including a deferred rent period and a leasehold improvement allowance	3,223,000
Leasehold improvement allowance	3,223,000
Stand by letter of credit decreased	419,000			1,384,000
Litigation, net		3,400,000
Reimburse amount		2,500,000
Settlement payment from research affiliates		700,000
Loss contingency amount reimburse by insurance carrier		200,000
Litigation expenses			$ 200,000