Description of Business and Summary of Significant Accounting Policies - Summary of Fair Value Maturities for Financial Asset (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Fair Value Disclosures [Abstract]
Cash equivalents and marketable securities, Total	$ 59,769
Cash equivalents and marketable securities, Less than 1 year	55,377
Cash equivalents and marketable securities, 1-5 years	$ 4,392