XML 56 R39.htm IDEA: XBRL DOCUMENT v3.10.0.1
Assets and Liabilities Measured at Fair Value (Detail) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value $ 119,053 $ 37,638
Money Market Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [1] 29,090 14,334
Restricted cash    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value 50 [2] 5,333 [3]
Federal Agency Securities | Cash and Cash Equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [1] 999  
Federal Agency Securities | Short-Term Investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [4] 14,775 1,500
U.S. Treasury Securities | Short-Term Investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [4] 74,139 16,471
Fair Value, Inputs, Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value 103,279 36,138
Fair Value, Inputs, Level 1 | Money Market Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [1] 29,090 14,334
Fair Value, Inputs, Level 1 | Restricted cash    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value 50 [2] 5,333 [3]
Fair Value, Inputs, Level 1 | U.S. Treasury Securities | Short-Term Investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [4] 74,139 16,471
Fair Value, Inputs, Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value 15,774 1,500
Fair Value, Inputs, Level 2 | Federal Agency Securities | Cash and Cash Equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [1] 999  
Fair Value, Inputs, Level 2 | Federal Agency Securities | Short-Term Investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, fair value [4] $ 14,775 $ 1,500
[1] Included in cash and cash equivalents on accompanying consolidated balance sheets.
[2] $0.05 million of restricted cash serves as collateral for the Company’s corporate credit card.
[3] $5.3 million of restricted cash in the Indenture (see Note 9) serves as full collateral for the redeemable convertible notes.
[4] Included in short-term investments on accompanying consolidated balance sheets and are classified as available-for-sale securities.