Investments (Allowance for Losses) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning of year	$ 482	$ 1,256
Addition to (release of) allowance for losses	(11)	(774)
Total ending balance (less than for Agricultural loans)	471	482
Agricultural Property Loans
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning of year	100
Total ending balance (less than for Agricultural loans)	$ 100	$ 100