OTHER COMPREHENSIVE INCOME (Amounts Reclassified from Accumulated Other Comprehensive Income to Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ (33,035)	$ (33,244)	$ (65,969)	$ (71,018)
Other nonoperating expense	2,466	3,339	5,595	8,421
Benefit from income taxes	47,598	40,046	58,291	35,143
Total	197,558	159,652	260,857	212,631
Reclassification From AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total	392	1,144	682	2,301
Interest Rate Hedge Losses [Member] | Reclassification From AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	76	71	151	160
Benefit from income taxes	(20)	(19)	(40)	(42)
Total	56	52	111	118
Pension and Postretirement Plan Actuarial Loss and Prior Service Cost [Member] | Reclassification From AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other nonoperating expense	386	1,477	772	2,953
Benefit from income taxes	(50)	(385)	(201)	(770)
Total	$ 336	$ 1,092	$ 571	$ 2,183