Reinsurance and Policy Benefits and Losses, Claims and Loss Expenses Payable (Insurance Subsidiaries Activity) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Year ended December 31,
Direct amount (a) - Life insurance in force		$ 947,720	$ 937,779	$ 927,647
Ceded to other companies - Life insurance in force		248	249	397
Assumed from other companies - Life insurance in force		876,865	915,769	949,413
Net amount (a) - Life insurance in force		$ 1,824,337	$ 1,853,299	$ 1,876,663
Percentage of amount assumed to net - Life insurance in force		48.00%	49.00%	51.00%
Direct amount (a)	[1]	$ 199,512	$ 202,535	$ 198,884
Ceded to other companies		368	310	320
Assumed from other companies		12,659	13,688	14,118
Net amount (a)	[1]	211,803	215,913	212,682
Premiums earned: Life [Member]
Year ended December 31,
Direct amount (a)	[1]	51,227	50,251	49,126
Ceded to other companies		4		8
Assumed from other companies		9,880	10,626	11,310
Net amount (a)	[1]	$ 61,103	$ 60,877	$ 60,428
Percentage of amount assumed to net		16.00%	17.00%	19.00%
Premiums earned: Accident and health [Member]
Year ended December 31,
Direct amount (a)	[1]	$ 90,396	$ 99,450	$ 99,354
Ceded to other companies		295	310	312
Assumed from other companies		1,977	2,263	2,545
Net amount (a)	[1]	$ 92,078	$ 101,403	$ 101,587
Percentage of amount assumed to net		2.00%	2.00%	3.00%
Premiums earned: Annuity [Member]
Year ended December 31,
Direct amount (a)	[1]	$ 728	$ 505	$ 392
Ceded to other companies
Assumed from other companies		794	794	255
Net amount (a)	[1]	$ 1,522	$ 1,299	$ 647
Percentage of amount assumed to net		52.00%	61.00%	39.00%
Premiums earned: Property and casualty [Member]
Year ended December 31,
Direct amount (a)	[1]	$ 57,161	$ 52,329	$ 50,012
Ceded to other companies		69
Assumed from other companies		8	5	8
Net amount (a)	[1]	$ 57,100	$ 52,334	$ 50,020
Percentage of amount assumed to net		0.00%	0.00%	0.00%

[1] Balances are reported net of inter-segment transactions