Fair Value Measurement (Details) - USD ($)	Sep. 30, 2017	Jun. 30, 2017
Available-for-Sale Securities
Mutual funds	$ 8,158,000	$ 9,043,000
Mutual funds, fair value	8,158,000	9,043,000
Held-to-maturity securities, maturities less than 1 year	1,654,000	1,607,000
Held-to-maturity securities, maturities less than 1 year, fair value	1,654,000	1,607,000
Held-to-maturity securities, remaining maturities from 1-3 years	881,000	1,441,000
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	881,000	1,441,000
Held-to-maturity securities, maturities from 91-360 days	250,000	250,000
Held-to-maturity securities, maturities from 91-360 days, fair value	250,000	250,000
Held-to-maturity securities, maturities over 360 days	547,000	549,000
Held-to-maturity securities, maturities over 360 days, fair value	547,000	549,000
Investments	11,490,000	12,890,000
Investments, fair value	11,490,000	12,890,000
Level 1
Available-for-Sale Securities
Mutual funds, fair value	8,158,000	9,043,000
Held-to-maturity securities, maturities less than 1 year, fair value	0	0
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	0	0
Held-to-maturity securities, maturities from 91-360 days, fair value	0	0
Held-to-maturity securities, maturities over 360 days, fair value	0	0
Investments, fair value	8,158,000	9,043,000
Level 2
Available-for-Sale Securities
Mutual funds, fair value	0	0
Held-to-maturity securities, maturities less than 1 year, fair value	1,654,000	1,607,000
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	881,000	1,441,000
Held-to-maturity securities, maturities from 91-360 days, fair value	250,000	250,000
Held-to-maturity securities, maturities over 360 days, fair value	547,000	549,000
Investments, fair value	3,332,000	3,847,000
Level 3
Available-for-Sale Securities
Mutual funds, fair value	0	0
Held-to-maturity securities, maturities less than 1 year, fair value	0	0
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	0	0
Held-to-maturity securities, maturities from 91-360 days, fair value	0	0
Held-to-maturity securities, maturities over 360 days, fair value	0	0
Investments, fair value	$ 0	$ 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

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No definition available.

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

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

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- Definition

Held-to-maturity Securities, Debt Maturities, after One Through Three Years, Fair Value

+ References

No definition available.

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- Definition

Held-to-maturity Securities, Debt Maturities, after One Through Three Years, Net Carrying Amount

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No definition available.

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- Definition

This element represents the carrying value of the mutual funds.

+ References

No definition available.

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This element represents amount of fair value for mutual funds.

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- Definition

Fair value of held-to-maturity debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-Subparagraph (a)
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- Definition

Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year following the latest fiscal year.

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- Definition

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

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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