Commitments and Contingencies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended	0 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Aug. 31, 2013 Investment in Debt Securities [Member]
Operating Leased Assets [Line Items]
Operating leases expenses	$ 826	$ 362
Period in which office lease expires	Jan. 01, 2014		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
Leasehold improvement allowance	3,223
Stand by letter of credit decreased			$ 419	$ 1,384