Employee Benefit Plans (Employee Benefits Charged To Operating Expenses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Total employee benefits	$ 71,297	$ 67,376	$ 66,470
Payroll Taxes [Member]
Total employee benefits	25,712	24,402	23,210
Medical Plans [Member]
Total employee benefits	27,030	25,143	25,497
401K Plan [Member]
Total employee benefits	14,986	14,244	13,562
Other [Member]
Total employee benefits	2,918	2,883	3,214
Pension Plans [Member]
Total employee benefits	$ 651	$ 704	$ 987