Fair value of financial instruments Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | 3 Months Ended | |
Sep. 30, 2019 | Sep. 30, 2018 | Jun. 30, 2019 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | $ 4,930 | | $ 1,288 |
Total short-term investments | 102,515 | | 70,854 |
Marketable equity securities | | | 1,349 |
Short-term investments | 102,515 | | 72,203 |
Cash equivalents and short-term investments | 107,445 | | 73,491 |
Accretion of net premium on short-term investments | 12 | $ 5 | |
Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 2,721 | | 790 |
Total short-term investments | 6,127 | | 3,572 |
Marketable equity securities | | | 1,349 |
Short-term investments | | | 4,921 |
Cash equivalents and short-term investments | 8,848 | | 5,711 |
Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 2,209 | | 498 |
Total short-term investments | 96,388 | | 67,282 |
Marketable equity securities | | | 0 |
Short-term investments | | | 67,282 |
Cash equivalents and short-term investments | 98,597 | | 67,780 |
Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | 0 |
Total short-term investments | 0 | | 0 |
Marketable equity securities | | | 0 |
Short-term investments | | | 0 |
Cash equivalents and short-term investments | 0 | | 0 |
U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 6,127 | | 3,572 |
U.S. treasury securities | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 6,127 | | 3,572 |
U.S. treasury securities | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
U.S. treasury securities | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 4,551 | | 3,009 |
U.S. agency securities | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
U.S. agency securities | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 4,551 | | 3,009 |
U.S. agency securities | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 18,354 | | 12,413 |
Asset-backed securities | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Asset-backed securities | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 18,354 | | 12,413 |
Asset-backed securities | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 8,034 | | 4,140 |
Municipal securities | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Municipal securities | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 8,034 | | 4,140 |
Municipal securities | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 1,736 | | 1,986 |
Commercial paper | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Commercial paper | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 1,736 | | 1,986 |
Commercial paper | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 63,713 | | 45,734 |
Corporate bonds | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Corporate bonds | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 63,713 | | 45,734 |
Corporate bonds | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Total short-term investments | 0 | | 0 |
Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 650 | | 790 |
Money market mutual funds | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 650 | | 790 |
Money market mutual funds | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | 0 |
Money market mutual funds | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | 0 |
U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 2,071 | | |
U.S. treasury securities | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 2,071 | | |
U.S. treasury securities | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | |
U.S. treasury securities | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | |
Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 1,994 | | 498 |
Commercial paper | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | 0 |
Commercial paper | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 1,994 | | 498 |
Commercial paper | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | $ 0 |
Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 215 | | |
Corporate bonds | Quoted Prices in Active Markets for Identical Assets | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 0 | | |
Corporate bonds | Significant Other Observable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | 215 | | |
Corporate bonds | Significant Unobservable Inputs | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Cash equivalents | $ 0 | | |