Note 5 - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Millions	Jun. 30, 2016	Jun. 30, 2015
Money Market Funds [Member]
At Cost	$ 1.5	$ 6.3
Unrealized Gains
Unrealized (Losses)
Fair Value	1.5	6.3
US Government Agencies Debt Securities [Member]
At Cost	2.0	6.5
Unrealized Gains
Unrealized (Losses)
Fair Value	2.0	6.5
US Treasury Securities [Member]
At Cost	7.0	9.6
Unrealized Gains
Unrealized (Losses)		(0.1)
Fair Value	7.0	9.5
Corporate Note Securities [Member]
At Cost	2.9	2.9
Unrealized Gains	0.1
Unrealized (Losses)
Fair Value	3.0	2.9
Certificates of Deposit [Member]
At Cost	7.3	1.9
Unrealized Gains
Unrealized (Losses)
Fair Value	7.3	1.9
At Cost	20.7	27.2
Unrealized Gains	0.1
Unrealized (Losses)		(0.1)
Fair Value	$ 20.8	$ 27.1

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

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

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

This item represents the cost of debt and equity 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 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 investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or 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=65884222&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=66010992&loc=d3e26626-111562

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