Fair Value Measurements - Contractual Maturity Date of Short-Term Investments (Detail) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Contractual Maturity Date of Short-Term Investments [Abstract]
Due within one year	$ 195,003	$ 205,250
Due between one and five years	16,489	5,979
Total	$ 211,492	$ 211,229