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, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in Fair Value of Plan Assets
Balance at beginning of year	$ 72,296	$ 75,956
Actual return on plan assets	(1,909)	(984)
Company contribution	2,025	2,900
Benefit payments	(6,355)	(5,576)
Balance at end of year	66,057	72,296	$ 75,956
Change in Benefit Obligations
Balance at beginning of year	105,942	110,923
Interest cost	4,153	4,055	4,144
Service cost	600
Assumption change (gain) loss	308	(3,838)
Actuarial (gain) loss	(967)	378
Benefit payments	(6,355)	(5,576)
Balance at end of year	$ 103,681	$ 105,942	$ 110,923