Employee Benefit Plans (Changes in Fair Value of Plan Assets and Plan Benefit Obligations and Funded Status of Plan) (Details) - Employee Pension Plans [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in Fair Value of Plan Assets
Balance at beginning of year	$ 75,956	$ 72,617
Actual return on plan assets	(984)	3,711
Company contribution	2,900	5,213
Benefit payments	(5,576)	(5,585)
Balance at end of year	72,296	75,956	$ 72,617
Change in Benefit Obligations
Balance at beginning of year	110,923	95,178
Interest cost	4,055	4,144	3,710
Assumption change loss (gain)	(3,838)	17,054
Actuarial loss	378	132
Benefit payments	(5,576)	(5,585)
Balance at end of year	$ 105,942	$ 110,923	$ 95,178