Income Taxes (Details 2) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Other employee benefits	$ 19,945	$ 17,846
Pension and other postretirement benefits	48,897	55,443
Allowance for management fee returned on cancelled policies	4,375	3,850
Other	546	44
Total deferred tax assets	73,763	77,183
Deferred tax liabilities:
Depreciation	17,843	17,290
Prepaid expenses	6,929	8,090
Limited partnerships	5,822	10,526
Unrealized gains on investments	1,360	3,691
Other	1,123	265
Total deferred tax liabilities	33,077	39,862
Net deferred tax asset	$ 40,686	$ 37,321