Balance Sheet Accounts (Summary of Cash and Marketable Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Cash	$ 140,643	$ 121,139
Marketable securities (consisting of available-for-sale securities)	428	1,459
Total cash and marketable securities	$ 141,071	$ 122,598

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.

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

Name:	us-gaap_Cash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant