PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 31, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost		$ 892,000	$ 996,000	$ 2,675,000	$ 2,988,000
Interest Cost		2,233,000	2,083,000	6,699,000	6,251,000
Expected Return on Plan Assets		(2,488,000)	(2,759,000)	(7,463,000)	(8,278,000)
Amortizations:
Prior Service Cost		39,000	40,000	117,000	119,000
Actuarial Loss		1,730,000	1,979,000	5,190,000	5,938,000
Net Periodic Benefit Cost		2,406,000	2,339,000	7,218,000	7,018,000
Capitalized Benefit Cost		(1,251,000)	(1,216,000)	(3,651,000)	(3,649,000)
Deferred Benefit Cost		(161,000)	(341,000)	(483,000)	(666,000)
Total Net Periodic Benefit Expense		994,000	782,000	3,084,000	2,703,000
Contributions	$ 12,000,000			0
Estimated future contributions				0
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost		106,000	186,000	318,000	558,000
Interest Cost		325,000	495,000	977,000	1,486,000
Expected Return on Plan Assets		(386,000)	(499,000)	(1,159,000)	(1,496,000)
Amortizations:
Prior Service Cost		(43,000)	102,000	(129,000)	304,000
Actuarial Loss		138,000	224,000	414,000	671,000
Net Periodic Benefit Cost		140,000	508,000	421,000	1,523,000
Capitalized Benefit Cost		(73,000)	(264,000)	(219,000)	(792,000)
Deferred Benefit Cost		0	(89,000)	0	(168,000)
Total Net Periodic Benefit Expense		$ 67,000	$ 155,000	202,000	$ 563,000
Defined benefit plan regulatory obligation to contribute to the plan during the period				3,600,000
Supplemental Employee Retirement Plans, Defined Benefit
Amortizations:
Estimated future contributions				$ 2,200,000