Real Estate and Lending Activities - Schedule of Revenue by Operator (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 134,999	$ 95,961
Revenue [Member] | Credit Concentration Risk [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 134,999	$ 95,961
Percentage of Total Revenue	100.00%	100.00%
Revenue [Member] | Credit Concentration Risk [Member] | Prime [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 28,897	$ 24,021
Percentage of Total Revenue	21.40%	25.00%
Revenue [Member] | Credit Concentration Risk [Member] | Median [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 23,510	$ 15,210
Percentage of Total Revenue	17.40%	15.90%
Revenue [Member] | Credit Concentration Risk [Member] | Capella [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 21,477
Percentage of Total Revenue	15.90%
Revenue [Member] | Credit Concentration Risk [Member] | Ernest [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 16,406	$ 14,700
Percentage of Total Revenue	12.20%	15.30%
Revenue [Member] | Credit Concentration Risk [Member] | Adeptus Health [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 7,676	$ 3,405
Percentage of Total Revenue	5.70%	3.60%