PENSION AND OTHER POST-RETIREMENT BENEFIT PLANS - AMOUNTS EXPECTED TO BE AMORTIZED FROM AOCI INTO NET PERIODIC BENEFIT (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss (gain)	$ 33,567
Amortization of prior service (credit) cost	(5,822)
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss (gain)	(1)
Amortization of prior service (credit) cost	$ 747