Investments and cash at fair value.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in 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 (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 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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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-SubTopic 10
-Section 45
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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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- Definition

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. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Fair value portion 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. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Sum of investments and unrestricted cash as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1,2)
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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.

+ References

No definition available.

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Marketable Investment Securities - Schedule of Fair Value for Available-for-Sale Securities by Major Security Type and Class of Security (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 108.1	$ 68.5	$ 134.7	$ 64.1
Amortized cost	218.3	238.4
Gross unrealized holding gains		0.5
Gross unrealized holding losses	(0.3)
Estimated fair value	218.0	238.9
Amortized cost	218.3	238.4
Estimated fair value	218.0	238.9
Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	38.6	50.8
Gross unrealized holding gains		0.2
Gross unrealized holding losses	(0.1)
Estimated fair value	38.5	51.0
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	55.7	85.4
Gross unrealized holding gains		0.2
Gross unrealized holding losses	(0.1)
Estimated fair value	55.6	85.6
Federal Agency Issues [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	12.6	25.5
Gross unrealized holding losses	(0.1)
Estimated fair value	12.5	25.5
Cash [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	81.3	66.1
Estimated fair value	81.3	66.1
Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	26.8	2.4
Estimated fair value	26.8	2.4
Total Cash and Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	108.1	68.5
Estimated fair value	108.1	68.5
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	3.3	8.2
Gross unrealized holding gains		0.1
Estimated fair value	$ 3.3	$ 8.3