Capital Stock - Reserved Shares of Common Stock (Detail) - shares	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Equity [Abstract]
Issuance in connection with outstanding stock options	1,949,089	2,244,363	1,675,506	1,989,237
Issuance in connection with restricted stock units outstanding	1,898,025	2,279,081	1,044,651
Reserved for future stock option and restricted stock unit grants	650,527	1,166,742
Reserved for future issuance under the employee stock purchase plan	1,049,524	895,268
Total	5,547,165	6,585,454