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Stockholders' Equity and Stock-Based Compensation - Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) [Member]
9 Months Ended
Sep. 30, 2017
$ / shares
shares
Activity for RSUs [Roll Forward]  
Number of units Beginning balance (in shares) | shares 819,785
Number of units, Granted (in shares) | shares 340,070
Number of units, Released (in shares) | shares (356,619)
Number of units, Cancelled (in shares) | shares (44,046)
Number of units, Ending balance (in shares) | shares 759,190
Weighted Average Fair Value for RSUs [Roll Forward]  
Weighted Average Fair Value, Beginning balance (in dollars per share) | $ / shares $ 16.79
Weighted Average Fair Value, Granted (in dollars per share) | $ / shares 27.29
Weighted Average Fair Value, Released (in dollars per share) | $ / shares 16.79
Weighted Average Fair Value, Cancelled (in dollars per share) | $ / shares 17.21
Weighted Average Fair Value, Ending balance (in dollars per share) | $ / shares $ 21.48