Mortgage Loans on Real Estate (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of mortgage loans:
Balance at beginning of year	$ 485,735	$ 635,492	$ 188,651
Additions:
New mortgage loans	6,706	8,223	524,088
Draws on existing loans	58,224	92,815	30,550
Total additions	64,930	101,038	554,638
Deductions:
Collections of principal	(180,135)	(191,134)	(80,552)
Conversions of real property	0	(45,044)	(23,288)
Charge Off	(71,535)	(3,053)	0
Total deductions	(251,670)	(239,231)	(103,840)
Change in balance due to foreign currency translation	7,125	(11,564)	(3,957)
Balance at end of year	$ 306,120	$ 485,735	$ 635,492