Real Estate and Lending Activities - Acquisitions - Additional Information (Detail) - Germany [Member] - Rehabilitation Hospital with Covenant Health System [Member] € in Millions			5 Months Ended
Jun. 06, 2018 Hospital	Jan. 30, 2017 EUR (€)	Jan. 30, 2017 EUR (€) Hospital
Business Acquisition [Line Items]
Purchase price of acquisition \| €		€ 8.4	€ 44.1
Number of facilities acquired \| Hospital	4		6

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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