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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2018 | Jun. 30, 2018
ASC 606 |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |
Reduction in revenue classified as bad debt expense | $ 8.0 | $ 16.0 |  |
Increased accounts receivable and retained earnings balances |  |  |  | $ 1.2
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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