Fair Value Measurements (Tables)
 12 Months Ended
Dec. 31, 2015
Fair Value Disclosures [Abstract]  
Summary of Financial Assets and Liabilities Measured on Recurring Basis at Fair Value

A summary of the financial assets and liabilities that are measured on a recurring basis at fair value as of December 31, 2015 and 2014, is as follows (in thousands):

 

 

 

 

 

 

 

Fair Value Measurements Using

 

 

 

Carrying

 

 

Quoted Prices in

Active Markets

for Identical

Assets

 

 

Significant

Other

Observable

Inputs

 

 

Significant

Unobservable

Inputs

 

 

 

Value

 

 

(Level 1)

 

 

(Level 2)

 

 

(Level 3)

 

December 31, 2015

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Money market funds

 

$

75,325

 

 

$

—

 

 

$

75,325

 

 

$

—

 

December 31, 2014

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Money market funds

 

$

50,541

 

 

$

—

 

 

$

50,541

 

 

$

—

 

 
Reconciliation of Company's Liabilities Measured at Fair Value on Recurring Basis Using Unobservable Inputs (Level 3)

The reconciliation of the Company’s liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) is as follows:

 

 

 

Preferred Stock Warrant

 

 

 

Series B

 

 

Series C

 

 

Series D

 

 

Total

 

Balance — December 31, 2013

 

 

4

 

 

 

386

 

 

 

538

 

 

 

928

 

Fair value reclassified to additional paid-in capital in connection

   with the completion of the  IPO on April 15, 2014

 

 

(4

)

 

 

(386

)

 

 

(538

)

 

 

(928

)

Balance — December 31, 2014

 

$

—

 

 

$

—

 

 

$

—

 

 

$

—

 

 
Fair Value of Stock Warrants Calculated using Black-Scholes Assumptions

The Company’s warrants were valued using the Black-Scholes option-pricing model.  The fair values were derived by applying the following assumptions:

 

 

 

December 31, 2013

Expected life

 

4-8 years

Risk-free interest rate

 

2.90%

Expected volatility

 

64%-84%

Expected dividend rate

 

—%