Other Income, Net

12 Months Ended

Dec. 31, 2017

Other Income and Expenses [Abstract]

Other Income, Net

Other Income (Expense), Net

Other income (expense), net for the years ended Dec. 31 consisted of the following:

(Thousands of Dollars)	2017			2016			2015
Interest income	$	2,407		$	129		$	129
Other nonoperating income	—			5			11
Insurance policy expense	(48		)	(43		)	(40		)
Other nonoperating expense	—			—			(106		)
Other income (expense), net	$	2,359		$	91		$	(6	)