Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Total [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance January 1, 2016	$ (10,739)	$ (7,475)
Other comprehensive income (loss) before reclassifications	6,245	(2,578)
Amounts reclassified from accumulated other comprehensive income	4	4
Net current period other comprehensive income (loss)	6,249	(2,574)
Ending balance June 30, 2016	(4,490)	(10,049)
Unrealized Gains (Losses) on Available-For-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance January 1, 2016	(5,176)	(3,017)
Other comprehensive income (loss) before reclassifications	6,989	(2,515)
Amounts reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	6,989	(2,515)
Ending balance June 30, 2016	1,813	(5,532)
Interest Rate Swaps [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance January 1, 2016	(466)	(324)
Other comprehensive income (loss) before reclassifications	(690)	(63)
Amounts reclassified from accumulated other comprehensive income	4	4
Net current period other comprehensive income (loss)	(686)	(59)
Ending balance June 30, 2016	(1,152)	(383)
Defined Benefit Plan Items [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance January 1, 2016	(5,097)	(4,134)
Other comprehensive income (loss) before reclassifications	(54)	0
Amounts reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	(54)	0
Ending balance June 30, 2016	$ (5,151)	$ (4,134)