Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments (Details 2)

v3.8.0.1
Financial Instruments (Details 2)
$ in Thousands
Dec. 31, 2016
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis $ 93,129
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (39)
Available-for-sale Securities 93,090
Money Market Funds [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis 39,181
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax 0
Available-for-sale Securities 39,181
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 39,181
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Contingent Consideration [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Business Combination, Contingent Consideration, Liability, Noncurrent 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 39,181
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 53,909
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Contingent Consideration [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Business Combination, Contingent Consideration, Liability, Noncurrent 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 27,993
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 25,916
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Contingent Consideration [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Business Combination, Contingent Consideration, Liability, Noncurrent 375
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 0
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 93,090
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Contingent Consideration [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Business Combination, Contingent Consideration, Liability, Noncurrent 375
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 27,993
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 25,916
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Money Market Funds [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities 39,181
Corporate Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis 25,923
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (7)
Available-for-sale Securities 25,916
US Government Agencies Debt Securities [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis 28,025
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (32)
Available-for-sale Securities 27,993
Cash and Cash Equivalents [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis 39,181
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax 0
Available-for-sale Securities 39,181
Investments [Member]  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Available-for-sale Securities, Amortized Cost Basis 53,948
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (39)
Available-for-sale Securities $ 53,909