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Balance Sheet Accounts (Summary of Cash and Marketable Securities) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Jun. 30, 2018 | Mar. 31, 2018 | Jun. 30, 2017
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Organization Consolidation And Presentation Of Financial Statements [Abstract] |  |  |  |
Cash | $ 156,813 | $ 121,139 | $ 103,177 | $ 130,450
Marketable securities (consisting of available-for-sale securities) | 262 | 1,459 |  |
Total cash and marketable securities | $ 157,075 | $ 122,598 |  |

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- Definition Cash and marketable Securities. + References No definition available. + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of investment in marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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