Other Income, Net (Tables)

12 Months Ended

Dec. 31, 2016

Other Income and Expenses [Abstract]

Other Income, Net

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

(Thousands of Dollars)	2016			2015			2014
Interest income	$	1,860		$	753		$	1,470
Other nonoperating income	2,241			2,408			3,601
Insurance policy expense	(281		)	(197		)	(806		)
Other nonoperating expense	(3		)	—			—
Other income, net	$	3,817		$	2,964		$	4,265