Fair Value Measurements
9 Months Ended
Sep. 30, 2014
Fair Value Disclosures [Abstract]  
Fair Value Measurements
Fair Value Measurements
The following tables present information about the Company’s financial assets measured at fair value on a recurring basis as of September 30, 2014, and December 31, 2013, and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value. As a basis for categorizing inputs, the Company uses a three-tier fair value hierarchy, which prioritizes the inputs used to measure fair value from market-based assumptions to entity specific assumptions:
Level 1: Quoted prices in active markets for identical assets or liabilities;
Level 2: Inputs, other than level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and
Level 3: Unobservable inputs that are supported by little or no market activity, which require the Company to develop its own assumptions.
Assets measured at fair value on a recurring basis as of September 30, 2014 are as follows (in thousands):
 
Balance as of
September 30,
2014
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant
Other
Observable
Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Assets:
 
 
 
 
 
 
 
Money market funds
$
7,445

 
$
7,445

 
$

 
$

Commercial paper
5,250

 

 
5,250

 

Corporate debt securities
42,053

 

 
42,053

 

Total assets
$
54,748

 
$
7,445

 
$
47,303

 
$

Assets measured at fair value on a recurring basis as of December 31, 2013 are as follows (in thousands):
 
Balance as of
December 31,
2013
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant
Other
Observable
Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Assets:
 
 
 
 
 
 
 
Money market funds
$
5,774

 
$
5,774

 
$

 
$

Commercial paper
15,246

 

 
15,246

 

Corporate debt securities
20,884

 

 
20,884

 

Total assets
$
41,904

 
$
5,774

 
$
36,130

 
$