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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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Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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