Rendering

Component: (Network and Table)
Network
100570 - Disclosure - Employee Benefits and Stock-based Compensation - Restricted Stock and Restricted Stock Units Activities (Detail)
(http://www.ambarella.com/20170131/taxonomy/role/DisclosureEmployeeBenefitsAndStockBasedCompensationRestrictedStockAndRestrictedStockUnitsActivitiesDetail)
TableSchedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Slicers (applies to each fact value in each table cell)
Reporting Entity [Axis]0001280263 (http://www.sec.gov/CIK)
Award TypeRestricted stock and restricted stock units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]Period [Axis]
2016-02-01 - 2017-01-31
2015-02-01 - 2016-01-31
2014-02-01 - 2015-01-31
Shares, Unvested, beginning balance
2,495,488  
1,980,448  
1,410,089  
Shares, Granted
676,598  
1,314,387  
1,111,204  
Shares, Vested
(955,230) 
(769,779) 
(484,296) 
Shares, Forfeited
(41,183) 
(29,568) 
(56,549) 
Shares, Unvested, ending balance
2,175,673  
 
2,495,488  
 
1,980,448  
 
Weighted-Average Grant-Date Fair Value, Unvested, beginning balance
47.04  
26.82  
14.02  
Weighted-Average Grant-Date Fair Value, Granted
67.68  
66.14  
38.60  
Weighted-Average Grant-Date Fair Value, Vested
39.28  
27.82  
17.39  
Weighted-Average Grant-Date Fair Value, Forfeited
52.49  
42.11  
19.93  
Weighted-Average Grant-Date Fair Value, Unvested, ending balance
56.76  
47.04  
26.82