Investments and cash at fair value.

No definition available.

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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

No definition available.

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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

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

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
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-Name Accounting Standards Codification
-Topic 210
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-Section 45
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-Name Accounting Standards Codification
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-SubTopic 10
-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

No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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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	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
Schedule of Available-for-sale Securities [Line Items]
Cash and cash equivalents, Amortized cost	$ 93.3	$ 110.9	$ 87.9	$ 102.4
Available-for-sale, Amortized cost	192.1	211.9
Gross unrealized holding losses	(0.4)	(0.6)
Available-for-sale, Estimated fair value	191.7	211.3
Amortized cost	192.1	211.9
Estimated fair value	191.7	211.3
Cash [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and cash equivalents, Amortized cost	75.3	95.6
Cash and cash equivalents, Estimated fair value	75.3	95.6
Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and cash equivalents, Amortized cost	18.0	15.3
Cash and cash equivalents, Estimated fair value	18.0	15.3
Total Cash and Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and cash equivalents, Amortized cost	93.3	110.9
Cash and cash equivalents, Estimated fair value	93.3	110.9
Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized cost	57.5	50.8
Gross unrealized holding losses	(0.3)	(0.3)
Available-for-sale, Estimated fair value	57.2	50.5
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized cost	23.4	29.3
Gross unrealized holding losses	(0.1)	(0.1)
Available-for-sale, Estimated fair value	23.3	29.2
Federal Agency Issues [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized cost	9.6	12.6
Gross unrealized holding losses		(0.1)
Available-for-sale, Estimated fair value	9.6	12.5
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized cost	8.3	8.3
Gross unrealized holding losses		(0.1)
Available-for-sale, Estimated fair value	$ 8.3	$ 8.2