Health Care, Pension and Other Benefits (Tables)

3 Months Ended

Mar. 31, 2012

Health Care, Pension and Other Benefits [Abstract]

Components of net periodic benefit costs for pension and other employee benefit plans

(Thousands of dollars)	Domestic Defined Benefit Pension Plans						Foreign Defined Benefit Pension Plans						Postretirement Benefits Other than  Pensions
	2012			2011			2012			2011			2012			2011
Three Months Ended March 31:
Net periodic benefit cost:
Service cost	$	4,732		$	4,007		$	892		$	935		$	736		$	874
Interest cost		4,331			4,707			1,725			1,070			3,380			3,895
Expected return on assets		(11,210	)		(11,610	)		(1,677	)		(665	)
Amortization of:
Prior service cost (credit)		398			409									(164	)		(164	)
Actuarial loss		5,486			4,877			251			215			429			626
Net periodic benefit cost	$	3,737		$	2,390		$	1,191		$	1,555		$	4,381		$	5,231