Real Estate and Lending Activities - Schedule of Gross Assets by Operator (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 5,117,933	$ 5,609,351
Assets, Total [Member] | Credit Concentration Risk [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 5,422,395	$ 6,035,922
Percentage of Total Gross Assets	100.00%	100.00%
Assets, Total [Member] | Credit Concentration Risk [Member] | Prime [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 1,126,654	$ 1,032,353
Percentage of Total Gross Assets	20.80%	17.10%
Assets, Total [Member] | Credit Concentration Risk [Member] | Median [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 1,054,368	$ 1,031,039
Percentage of Total Gross Assets	19.40%	17.10%
Assets, Total [Member] | Credit Concentration Risk [Member] | Ernest [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 584,411	$ 579,182
Percentage of Total Gross Assets	10.80%	9.60%
Assets, Total [Member] | Credit Concentration Risk [Member] | Adeptus Health [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 500,000	$ 500,000
Percentage of Total Gross Assets	9.20%	8.30%
Assets, Total [Member] | Credit Concentration Risk [Member] | RCCH [Member]
Investment And Revenue From External Customers [Line Items]
Total Gross Assets	$ 458,659	$ 1,059,989
Percentage of Total Gross Assets	8.50%	17.60%