Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 11,834	$ 27,480	$ 33,134	$ 50,778
Defined benefit plans:
Reclassification adjustment for losses included in net income (Pension termination)	0	0	0	2,519
Forward starting interest rate swaps:
Unrecognized loss on cash flow hedges	0	0	0	(1,684)
Reclassification adjustment for losses included in net income (Interest expense)	42	42	126	73
Total other comprehensive income	42	42	126	908
COMPREHENSIVE INCOME	$ 11,876	$ 27,522	$ 33,260	$ 51,686