Other Comprehensive Income

12 Months Ended

Dec. 31, 2016

Stockholders' Equity Note [Abstract]

Other Comprehensive Income

16. Other Comprehensive Income

Changes in accumulated other comprehensive (loss) income, net of tax, for the years ended Dec. 31, 2016 and 2015 were as follows:

	Year Ended Dec. 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 income (loss) before reclassifications	3			—		(7,783		)	(7,780		)
Losses reclassified from net accumulated other comprehensive loss	3,708			—		3,471			7,179
Net current period other comprehensive income (loss)	3,711			—		(4,312		)	(601		)
Accumulated other comprehensive (loss) income at Dec. 31	$	(51,151	)	$	110	$	(59,313	)	$	(110,354	)

	Year Ended Dec. 31, 2015
(Thousands of Dollars)	Gains and Losses on Cash Flow Hedges			Unrealized Gains and Losses on Marketable Securities		Defined Benefit Pension and Postretirement Items			Total
Accumulated other comprehensive (loss) income at Jan. 1	$	(57,628	)	$	110	$	(50,621	)	$	(108,139	)
Other comprehensive loss before reclassifications	(70		)	—		(7,906		)	(7,976		)
Losses reclassified from net accumulated other comprehensive loss	2,836			—		3,526			6,362
Net current period other comprehensive income (loss)	2,766			—		(4,380		)	(1,614		)
Accumulated other comprehensive (loss) income at Dec. 31	$	(54,862	)	$	110	$	(55,001	)	$	(109,753	)

Reclassifications from accumulated other comprehensive loss for the years ended Dec. 31, 2016 and 2015 were as follows:

	Amounts Reclassifiedfrom Accumulated Other ComprehensiveLoss
(Thousands of Dollars)	Year Ended Dec. 31, 2016				Year Ended Dec. 31, 2015
Losses (gains) on cash flow hedges:
Interest rate derivatives	$	5,859		(a)	$	4,515		(a)
Vehicle fuel derivatives	191			(b)	131			(b)
Total, pre-tax	6,050				4,646
Tax benefit	(2,342		)		(1,810		)
Total, net of tax	3,708				2,836
Defined benefit pension and postretirement losses (gains):
Amortization of net losses	5,912			(c)	6,132			(c)
Prior service credit	(256		)	(c)	(357		)	(c)
Total, pre-tax	5,656				5,775
Tax benefit	(2,185		)		(2,249		)
Total, net of tax	3,471				3,526
Total amounts reclassified, net of tax	$	7,179			$	6,362

^(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 9 for details regarding these benefit plans.