SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE (Narrative 1) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of period	$ 710,858	$ 671,232	$ 639,343
Additions during period - new mortgage loans or additional fundings	129,108	65,841	34,643
Deductions during period - collection of principal/other	(66,403)	(26,215)	(2,754)
Balance at close of period	773,563	710,858	671,232
Mortgage loans on real estate non cash interest paid-in kind	300	500
Mortgage loans on real estate non cash deed-in-lieu of foreclosure	$ 11,900
Amortizatoin of premium		$ 100	$ 1,200