SCHEDULE IV MORTGAGE LOANS ON REAL ESTATE - Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Mortgage loans on real estate
Balance at the beginning of the period	$ 165,656	$ 165,444	$ 39,299
New mortgage loans	60,209	3,027	124,387
Other additions	6,925	6,347	4,971
Land conveyance	670
Amortization of mortgage premium	(6)	(5)	(6)
Collections of principal	(15,408)	(9,155)	(1,933)
Loan loss reserve	(517)	(2)	(1,274)
Balance at the end of the period	$ 217,529	$ 165,656	$ 165,444