BENEFIT PLANS (Components of Net Periodic Benefit Cost, Amounts Recognized in Other Comprehensive Income, Weighted-Average Assumptions) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Plans, Defined Benefit [Member]
Components of Net Periodic Benefit Cost
Service cost	$ 1,213	$ 1,039	$ 3,638	$ 3,118
Interest cost	11,004	11,098	33,077	33,294
Expected return on plan assets	(13,683)	(12,701)	(41,051)	(38,102)
Settlement charge	2,031	0	2,031	0
Amortization of prior service cost (credit)	12	47	36	141
Amortization of actuarial loss	5,383	2,806	16,292	8,416
Net periodic pension/postretirement benefit cost	5,960	2,289	14,023	6,867
Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Pretax reclassifications from AOCI included in net periodic postretirement/pension benefit cost	7,426	2,853	18,359	8,557
Other Postretirement Benefit Plans, Defined Benefit [Member]
Components of Net Periodic Benefit Cost
Service cost	473	536	1,420	1,609
Interest cost	621	824	1,864	2,473
Curtailment gain	0	0	0	(3,832)
Amortization of prior service cost (credit)	(1,058)	(1,081)	(3,174)	(3,245)
Amortization of actuarial loss	9	57	28	170
Net periodic pension/postretirement benefit cost	45	336	138	(2,825)
Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Pretax reclassifications from AOCI included in net periodic postretirement/pension benefit cost	$ (1,049)	$ (1,024)	$ (3,146)	$ (6,907)