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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Millions | Mar. 31, 2020 | Jul. 01, 2019
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Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |
Operating lease right-of-use assets | $ 64.5 |
Operating lease liability current | 12.9 |
Operating lease liability noncurrent | 55.9 |
ASU 2016-02 |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |
Operating lease liability | 78.8 | $ 78.8
Operating lease right-of-use assets | $ 74.5 | 74.5
Operating lease liability current |  | 13.1
Operating lease liability noncurrent |  | $ 65.7
Assurex [Member] | Assurex Canada Ltd [Member] |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |
Non controlling interest ownership percentage by parent | 85.00% |
Centre For Addiction And Mental Health [Member] | Assurex Canada Ltd [Member] |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |
Non controlling interest ownership percentage by noncontrolling owners | 15.00% |

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