Fair Value of Financial Instruments - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018
Cash and cash equivalents:
Money market funds	$ 68.1	$ 86.8
Other current assets:
Securities	0.4	0.1
Other non-current assets:
Securities	81.8	66.9
Level 1
Cash and cash equivalents:
Money market funds	68.1	86.8
Other current assets:
Securities	0.4	0.1
Other non-current assets:
Securities	81.8	66.9
Liabilities:
Contingent consideration obligations	0.0	0.0
Level 2
Cash and cash equivalents:
Money market funds	0.0	0.0
Other current assets:
Securities	0.0	0.0
Other non-current assets:
Securities	0.0	0.0
Liabilities:
Contingent consideration obligations	0.0	0.0
Level 3
Cash and cash equivalents:
Money market funds	0.0	0.0
Other current assets:
Securities	0.0	0.0
Other non-current assets:
Securities	0.0	0.0
Liabilities:
Contingent consideration obligations	28.4	18.6
Fair Value, Measurements, Recurring
Other non-current assets:
Total	150.3	153.8
Fair Value, Measurements, Recurring \| Level 1
Other non-current assets:
Total	150.3	153.8
Liabilities:
Total	0.0	0.0
Fair Value, Measurements, Recurring \| Level 2
Other non-current assets:
Total	0.0	0.0
Liabilities:
Total	0.0	0.0
Fair Value, Measurements, Recurring \| Level 3
Other non-current assets:
Total	$ 0.0	$ 0.0

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Other Non Current Assets [Abstract]

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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.

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-Name Accounting Standards Codification
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-SubTopic 30
-Section 25
-Paragraph 6
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Fair value of financial and nonfinancial obligations.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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