Annual report pursuant to Section 13 and 15(d)

Stock Option and Purchase Plans - Fair Value for Options Granted under Employee Stock Purchase Plan (Detail)

v2.4.0.8
Stock Option and Purchase Plans - Fair Value for Options Granted under Employee Stock Purchase Plan (Detail)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]      
Dividend Yield 0.00% 0.00% 0.00%
Employee Stock [Member]
     
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]      
Risk-free Interest Rate 0.10% 0.17% 0.10%
Dividend Yield 0.00% 0.00% 0.00%
Volatility Factor 0.37% 0.37% 0.52%
Expected Life in Years 1 year 1 year 1 year