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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2017	Sep. 30, 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
Increased accounts receivable and retained earnings balances			$ 1.2
Assurex [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]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Non controlling interest ownership percentage by noncontrolling owners		15.00%

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- Definition

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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