Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 27,480	$ 4,153	$ 50,778	$ 14,127
Defined benefit plans:
Reclassification adjustment for losses included in net income (Pension termination)	0	0	2,519	0
Forward starting interest rate swaps:
Losses arising during the periods	0	0	(1,684)	0
Reclassification adjustment for losses included in net income (Interest expense)	42	0	73	0
Total other comprehensive income	27,522	4,153	51,686	14,127
Less: comprehensive income attributable to noncontrolling interests	0	(162)	0	(313)
COMPREHENSIVE INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ 27,522	$ 3,991	$ 51,686	$ 13,814