Product Warranties (Tables)

9 Months Ended

Sep. 30, 2014

Product Warranties Disclosures [Abstract]

Company's accrual for product warranty claims

Changes in the Company’s accrual for product warranty claims during the first nine months of 2014 and 2013, including customer satisfaction settlements, were as follows:

(Thousands of dollars)
	2014			2013
Balance at January 1	$	26,755		$	22,710
Charges to expense	25,250			18,916
Settlements	(26,297		)	(18,936		)
Balance at September 30	$	25,708		$	22,690