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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Jul. 01, 2019
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Operating lease right-of-use assets	$ 67.3
Operating lease liability current	12.8
Operating lease liability noncurrent	58.7
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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Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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-Publisher FASB
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-Topic 842
-SubTopic 20
-Section 45
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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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