Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 10,129	$ 4,458	$ 90,729	$ 88,317
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	204	182	612	548
Total other comprehensive loss	204	182	612	548
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	10,333	4,640	91,341	88,865
Net income attributable to noncontrolling interests	(10)	(7)	(143)	21
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 10,323	$ 4,633	$ 91,198	$ 88,886