Marketable Securities - Amortized Cost to Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 26,761
Gross Unrealized Gain		0
Gross Unrealized (Loss)		(16)
Fair Value	$ 4,941	26,745
U.S. Treasury Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		9,641
Gross Unrealized Gain		0
Gross Unrealized (Loss)		(9)
Fair Value		9,632
Certificate of Deposits
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		5,610
Gross Unrealized Gain		0
Gross Unrealized (Loss)		0
Fair Value		5,610
U.S. Government Sponsored Agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,941	6,751
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	0	(2)
Fair Value	$ 4,941	6,749
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,510
Gross Unrealized Gain		0
Gross Unrealized (Loss)		(5)
Fair Value		4,505
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		249
Gross Unrealized Gain		0
Gross Unrealized (Loss)		0
Fair Value		$ 249

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

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