Real Estate and Lending Activities - Schedule of Revenue by Operator (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 156,397	$ 134,999
Revenue [Member] | Credit Concentration Risk [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 156,397	$ 134,999
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	$ 31,511	$ 28,897
Percentage of Total Revenue	20.10%	21.40%
Revenue [Member] | Credit Concentration Risk [Member] | Steward [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 26,584
Percentage of Total Revenue	17.00%
Revenue [Member] | Credit Concentration Risk [Member] | MEDIAN [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 23,450	$ 23,510
Percentage of Total Revenue	15.00%	17.40%
Revenue [Member] | Credit Concentration Risk [Member] | Ernest [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 17,520	$ 16,406
Percentage of Total Revenue	11.20%	12.20%
Revenue [Member] | Credit Concentration Risk [Member] | RCCH [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 9,306	$ 21,477
Percentage of Total Revenue	6.00%	15.90%
Revenue [Member] | Credit Concentration Risk [Member] | Other Operators [Member]
Investment And Revenue From External Customers [Line Items]
Total Revenue	$ 48,026	$ 44,709
Percentage of Total Revenue	30.70%	33.10%