Health Care, Pension and Other Benefits (Tables)

9 Months Ended

Sep. 30, 2011

Health Care, Pension and Other Benefits [Abstract]

Health care, pension and other benefits

	Domestic Defined						Foreign Defined						Postretirement Benefits
	Benefit Pension Plans						Benefit Pension Plans						Other than Pensions
(Thousands of dollars)	2011			2010			2011			2010			2011			2010
Three Months Ended September 30:
Net periodic benefit cost:
Service cost	$	4,007		$	4,226		$	918		$	501		$	873		$	883
Interest cost		4,707			4,507			1,061			1,040			3,895			4,017
Expected return on assets		(11,610	)		(10,578	)		(662	)		(720	)
Amortization of:
Prior service cost (credit)		408			416						8			(164	)		(164	)
Actuarial loss		4,876			4,735			215			347			626			326
Net periodic benefit cost	$	2,388		$	3,306		$	1,532		$	1,176		$	5,230		$	5,062
Nine Months Ended September 30:
Net periodic benefit cost:
Service cost	$	12,021		$	12,679		$	2,814		$	1,490		$	2,621		$	2,649
Interest cost		14,121			13,521			3,225			3,079			11,685			12,050
Expected return on assets		(34,831	)		(31,733	)		(2,008	)		(2,130	)
Amortization of:
Prior service cost (credit)		1,226			1,246						22			(492	)		(492	)
Actuarial loss		14,630			14,207			650			1,027			1,878			978
Net periodic benefit cost	$	7,167		$	9,920		$	4,681		$	3,488		$	15,692		$	15,185