Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments (Details 2)

v3.7.0.1
Financial Instruments (Details 2) - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Amortized Cost Basis $ 72,332 $ 93,129
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (55) (39)
Available-for-sale Securities 72,277 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 8,640 39,181
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax 0 0
Available-for-sale Securities 8,640 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 8,640 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 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 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 8,640 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 63,637 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 25,981 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 37,656 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 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 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 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 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 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 72,277 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 25,981 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 37,656 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 8,640 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 37,676 25,923
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (20) (7)
Available-for-sale Securities 37,656 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 26,016 28,025
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (35) (32)
Available-for-sale Securities 25,981 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 8,640 39,181
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax 0 0
Available-for-sale Securities 8,640 39,181
Investments [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Amortized Cost Basis 63,692 53,948
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0 0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (55) (39)
Available-for-sale Securities $ 63,637 $ 53,909