Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 12,145	$ 17,916	$ 21,300	$ 23,298
Defined benefit plans:
Reclassification adjustment for losses included in net income (Pension termination)	0	2,519	0	2,519
Forward starting interest rate swaps:
Unrecognized loss on cash flow hedges	0	(961)	0	(1,684)
Reclassification adjustment for losses included in net income (Interest expense)	42	31	84	31
Total other comprehensive income	42	1,589	84	866
COMPREHENSIVE INCOME	$ 12,187	$ 19,505	$ 21,384	$ 24,164