Other Comprehensive Income (Loss) (Details 1) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease [Roll Forward]        
Beginning Balance $ 14,566 $ 627 $ (2,744) $ 2,867
Other comprehensive income before reclassifications (3,333) 5,515 14,260 3,883
Amounts reclassified from accumulated other comprehensive loss (273) (55) (556) (663)
Net current-period other comprehensive income (loss) (3,606) 5,460 13,704 3,220
Ending Balance 10,960 6,087 10,960 6,087
Other Comprehensive Income Employee Benefit Plans Adjustment Net Of Tax Period Increase Decrease [Roll Forward]        
Beginning Balance (27,833) (28,248) (28,257) (26,878)
Other comprehensive income before reclassifications 0 0 0 0
Amounts reclassified from accumulated other comprehensive (loss) income 213 133 637 (1,237)
Net current-period other comprehensive loss (income) 213 133 637 (1,237)
Ending Balance (27,620) (28,115) (27,620) (28,115)
Accumulated Other Comprehensive Income (Loss) Net Of Tax [Roll Forward]        
Beginning Balance (13,267) (27,621) (31,001) (24,011)
Other comprehensive income before reclassifications (3,333) 5,515 14,260 3,883
Amounts reclassified from accumulated other comprehensive (loss) income (60) 78 81 (1,900)
Other comprehensive income (3,393) 5,593 14,341 1,983
Ending Balance $ (16,660) $ (22,028) $ (16,660) $ (22,028)