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Fair Value Measurements - Schedule of Fair Value of Financial Assets (Detail) - USD ($) $ in Millions | Sep. 30, 2016 | Jun. 30, 2016
--- | --- | ---
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets and liability |  | $ (2.0) | $ 162.4
Contingent Consideration |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial liability |  | (141.5) | (10.4)
Money Market Funds |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets | [1] | 25.8 | 2.4
Corporate Bonds and Notes |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 45.5 | 51.0
Municipal Bonds |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 52.3 | 85.6
Federal Agency Issues |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 12.6 | 25.5
US Government Securities |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 3.3 | 8.3
Level 1 |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets and liability |  | 25.8 | 2.4
Level 1 | Money Market Funds |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets | [1] | 25.8 | 2.4
Level 2 |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets and liability |  | 113.7 | 170.4
Level 2 | Corporate Bonds and Notes |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 45.5 | 51.0
Level 2 | Municipal Bonds |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 52.3 | 85.6
Level 2 | Federal Agency Issues |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 12.6 | 25.5
Level 2 | US Government Securities |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets |  | 3.3 | 8.3
Level 3 |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial assets and liability |  | (141.5) | (10.4)
Level 3 | Contingent Consideration |  |  |
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] |  |  |
Total fair value of financial liability |  | $ (141.5) | $ (10.4)
[1] | Money market funds are primarily comprised of exchange traded funds and accrued interest

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