ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)

3 Months Ended

Mar. 31, 2015

Accumulated Other Comprehensive Income (Loss) [Line Items]

Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]

The following table sets forth the effect of reclassifications from accumulated other comprehensive income (loss) on our Statements of Income for the period indicated:

Details about Accumulated Other Comprehensive	Three Months Ended March 31,						Affected Line Item in the
Income (Loss) Components	2015			2014			Statements of Income
	(Thousands of dollars)
Pension and other postretirement benefit plan obligations (a)
Amortization of net loss	$	12,565		$	8,542
Amortization of unrecognized prior service cost	(373		)	(303		)
	12,192			8,239
Regulatory adjustments (b)	(11,964		)	(13,756		)
	228			(5,517		)	Income before income taxes
	(88		)	2,124			Income tax expense
Total reclassifications for the period	$	140		$	(3,393	)	Net income

(a) These components of accumulated other comprehensive income (loss) are included in the computation of net periodic benefit cost. See Note 7 for additional detail of our net periodic benefit cost.

(b) Regulatory adjustments represent pension and other postretirement benefit costs expected to be recovered through rates and are deferred as part of our regulatory assets. See Note 2 for additional disclosures of regulatory assets and liabilities.