Fair value of financial instruments (Details) - USD ($) $ in Thousands | 6 Months Ended | |
Dec. 31, 2016 | Dec. 31, 2015 | Jun. 30, 2016 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | $ 90,384 | | $ 95,318 |
Accretion of net premium on short-term investments | 237 | $ 381 | |
Short-term investments: | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 85,988 | | 88,277 |
Short-term investments: | U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,168 | | 5,929 |
Short-term investments: | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 1,263 | | 1,702 |
Short-term investments: | Asset-backed securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 8,227 | | 10,175 |
Short-term investments: | Municipal securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 9,015 | | 6,018 |
Short-term investments: | Commercial paper | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,243 | | 3,495 |
Short-term investments: | Foreign government securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 749 | | |
Short-term investments: | Corporate bonds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 60,323 | | 60,958 |
Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 4,396 | | 7,041 |
Cash equivalents | Money market mutual funds | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 4,396 | | 5,641 |
Cash equivalents | U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | | | 1,400 |
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 | 5,659 | | 7,343 |
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 | 1,263 | | 1,702 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments: | U.S. agency 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: | U.S. treasury securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 1,263 | | 1,702 |
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: | Foreign government securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 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 | 4,396 | | 5,641 |
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 | 4,396 | | 5,641 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash equivalents | U.S. agency securities | | | |
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 | 84,725 | | 87,975 |
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 | 84,725 | | 86,575 |
Significant Other Observable Inputs (Level 2) | Short-term investments: | U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 3,168 | | 5,929 |
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 | | 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 | 8,227 | | 10,175 |
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 | 9,015 | | 6,018 |
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 | 3,243 | | 3,495 |
Significant Other Observable Inputs (Level 2) | Short-term investments: | Foreign government securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 749 | | |
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 | 60,323 | | 60,958 |
Significant Other Observable Inputs (Level 2) | Cash equivalents | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | 0 | | 1,400 |
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 | U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | | | 1,400 |
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. agency 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: | U.S. treasury 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: | 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: | Foreign government 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: | 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 | U.S. agency securities | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Estimated Fair Value | | | $ 0 |