Reconciliation Between Effective Tax Rate and Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Federal income tax rate	34.00%	34.00%	34.00%
Research and development tax credits	1.40%	(0.60%)	54.60%
Valuation allowance	(12.40%)	(7.50%)	(507.40%)
Permanent Differences	(8.80%)	(25.90%)	450.00%
Other			(31.20%)
Foreign rate differential	(14.20%)
Effective tax rate