Other Comprehensive Income

3 Months Ended

Mar. 31, 2017

Stockholders' Equity Note [Abstract]

Other Comprehensive Income

Other Comprehensive Income

Changes in accumulated other comprehensive (loss) income, net of tax, for the three months ended March 31, 2017 and 2016 were as follows:

	Three Months Ended March 31, 2017
(Thousands of Dollars)	Gains and Losses on Cash Flow Hedges			Unrealized Gains and Losses onMarketable Securities		Defined Benefit Pension and Postretirement Items			Total
Accumulated other comprehensive (loss) income at Jan. 1	$	(51,151	)	$	110	$	(59,313	)	$	(110,354	)
Losses reclassified from net accumulated other comprehensive loss	825			—		948			1,773
Net current period other comprehensive income	825			—		948			1,773
Accumulated other comprehensive (loss) income at March 31	$	(50,326	)	$	110	$	(58,365	)	$	(108,581	)

	Three Months Ended March 31, 2016
(Thousands of Dollars)	Gains and Losses on Cash Flow Hedges			Unrealized Gains and Losses onMarketable Securities		Defined Benefit Pension and Postretirement Items			Total
Accumulated other comprehensive (loss) income at Jan. 1	$	(54,862	)	$	110	$	(55,001	)	$	(109,753	)
Other comprehensive loss before reclassifications	(4		)	—		(653		)	(657		)
Losses reclassified from net accumulated other comprehensive loss	938			—		864			1,802
Net current period other comprehensive income	934			—		211			1,145
Accumulated other comprehensive (loss) income at March 31	$	(53,928	)	$	110	$	(54,790	)	$	(108,608	)

Reclassifications from accumulated other comprehensive loss for the three months ended March 31, 2017 and 2016 were as follows:

	Amounts Reclassifiedfrom Accumulated Other ComprehensiveLoss
(Thousands of Dollars)	Three Months Ended March 31, 2017				Three Months Ended March 31, 2016
Losses on cash flow hedges:
Interest rate derivatives	$	1,359		(a)	$	1,485		(a)
Vehicle fuel derivatives	—			(b)	57			(b)
Total, pre-tax	1,359				1,542
Tax benefit	(534		)		(604		)
Total, net of tax	825				938
Defined benefit pension and postretirement losses:
Amortization of net loss	1,623			(c)	1,478			(c)
Prior service credit	(60		)	(c)	(64		)	(c)
Total, pre-tax	1,563				1,414
Tax benefit	(615		)		(550		)
Total, net of tax	948				864
Total amounts reclassified, net of tax	$	1,773			$	1,802

^(a)  Included in interest charges.

^(b)  Included in O&M expenses.

^(c)  Included in the computation of net periodic pension and postretirement benefit costs. See Note 12 for details regarding these benefit plans.