Fair Value Measurement (Details) - USD ($)	Sep. 30, 2018	Jun. 30, 2018
Available-for-Sale Securities
Mutual funds		$ 1,728,000
Held-to-maturity securities, maturities less than 1 year		1,328,000
Held-to-maturity securities, maturities from 91-360 days		495,000
Held-to-maturity securities, maturities over 360 days		50,000
Investments		3,601,000
Mutual funds, fair value		1,728,000
Held-to-maturity securities, maturities less than 1 year, fair value		1,328,000
Held-to-maturity securities, maturities from 91-360 days, fair value		495,000
Held-to-maturity securities, maturities over 360 days, fair value		50,000
Investments, fair value	$ 0	3,601,000
Level 1
Available-for-Sale Securities
Mutual funds, fair value		1,728,000
Held-to-maturity securities, maturities less than 1 year, fair value		0
Held-to-maturity securities, maturities from 91-360 days, fair value		0
Held-to-maturity securities, maturities over 360 days, fair value		0
Investments, fair value		1,728,000
Level 2
Available-for-Sale Securities
Mutual funds, fair value		0
Held-to-maturity securities, maturities less than 1 year, fair value		1,328,000
Held-to-maturity securities, maturities from 91-360 days, fair value		495,000
Held-to-maturity securities, maturities over 360 days, fair value		50,000
Investments, fair value		1,873,000
Level 3
Available-for-Sale Securities
Mutual funds, fair value		0
Held-to-maturity securities, maturities less than 1 year, fair value		0
Held-to-maturity securities, maturities from 91-360 days, fair value		0
Held-to-maturity securities, maturities over 360 days, fair value		0
Investments, fair value		$ 0

Held-To-Maturity Securities, Debt Maturities, 91 To 360 Days, Fair Value

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- Definition

Held-To-Maturity Securities, Debt Maturities, 91 To 360 Days, Net Carrying Amount

+ References

No definition available.

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- Definition

Held-To-Maturity Securities, Debt Maturities, Over 360 Days, Fair Value

+ References

No definition available.

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- Definition

Held-To-Maturity Securities, Debt Maturities, Over 360 Days, Net Carrying Amount

+ References

No definition available.

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- Definition

This element represents the carrying value of the mutual funds.

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No definition available.

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This element represents amount of fair value for mutual funds.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)(1)
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803

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Amount of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-Subparagraph (a)
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-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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