Annual report pursuant to Section 13 and 15(d)

Financial Instruments and Risk - Additional Information (Detail)

v3.3.1.900
Financial Instruments and Risk - Additional Information (Detail)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Schedule Of Cost Method Investments [Line Items]    
Average days to maturity of Company's portfolio of cash equivalents and marketable securities 61 days 174 days
Maximum [Member]    
Schedule Of Cost Method Investments [Line Items]    
Maturity period of securities 1 year