Fair value of financial instruments (Details) - USD ($) $ in Thousands | 3 Months Ended | |
Sep. 30, 2015 | Sep. 30, 2014 | Jun. 30, 2015 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | $ 104,401 | | $ 109,110 |
Amortization of net premium on short-term investments | 205 | $ 543 | |
Short-term investments | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 99,763 | | 101,195 |
Short-term investments | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 451 | | |
Short-term investments | Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 15,582 | | 16,983 |
Short-term investments | Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 9,286 | | 10,017 |
Short-term investments | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 4,244 | | 1,998 |
Short-term investments | Agency bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 8,975 | | 7,646 |
Short-term investments | Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 61,225 | | 64,551 |
Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 4,638 | | 7,915 |
Cash equivalents | Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,139 | | 7,915 |
Cash equivalents | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 1,499 | | |
Quoted Prices in Active Markets for Identical Assets (Level 1) | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,590 | | 7,915 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 451 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 451 | | |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Agency bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,139 | | 7,915 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash equivalents | Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,139 | | 7,915 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash equivalents | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | |
Significant Other Observable Inputs (Level 2) | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 100,811 | | 101,195 |
Significant Other Observable Inputs (Level 2) | Short-term investments | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 99,312 | | 101,195 |
Significant Other Observable Inputs (Level 2) | Short-term investments | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | |
Significant Other Observable Inputs (Level 2) | Short-term investments | Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 15,582 | | 16,983 |
Significant Other Observable Inputs (Level 2) | Short-term investments | Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 9,286 | | 10,017 |
Significant Other Observable Inputs (Level 2) | Short-term investments | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 4,244 | | 1,998 |
Significant Other Observable Inputs (Level 2) | Short-term investments | Agency bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 8,975 | | 7,646 |
Significant Other Observable Inputs (Level 2) | Short-term investments | Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 61,225 | | 64,551 |
Significant Other Observable Inputs (Level 2) | Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 1,499 | | 0 |
Significant Other Observable Inputs (Level 2) | Cash equivalents | Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Other Observable Inputs (Level 2) | Cash equivalents | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 1,499 | | |
Significant Unobservable Inputs (Level 3) | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | |
Significant Unobservable Inputs (Level 3) | Short-term investments | Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | Agency bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Short-term investments | Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 0 |
Significant Unobservable Inputs (Level 3) | Cash equivalents | Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | $ 0 |
Significant Unobservable Inputs (Level 3) | Cash equivalents | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | $ 0 | | |