PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Assets Within Our U.S. and Canadian Qualified and Registered Pension Plans (Details) - Qualified and Registered Plans [Member]	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(100.00%)	(100.00%)
Cash and short-term investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(5.80%)	(10.60%)
Fixed income investments, Corporate
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(21.50%)	(0.00%)
Government
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(8.60%)	(0.00%)
Hedge funds and related investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(36.90%)	(58.80%)
Private equity and related investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(21.90%)	(22.20%)
Derivative instruments, net
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(5.60%)	(8.70%)
Accrued liabilities
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	(0.30%)	(0.30%)