Benefit Plans and Other Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2012

Benefit Plans and Other Postretirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

Components of Net Periodic Benefit Cost

 

	Three Months Ended June 30
	2012				2011				2012				2011
									Postretirement Health
(Thousands of Dollars)			Pension Benefits								Care Benefits
Service cost		$	1,150			$	1,234			$	5			$	5
Interest cost			1,925				1,998				274				300
Expected return on plan assets			(2,634	)			(2,841	)			(12	)			(18	)
Amortization of transition obligation			-				-				43				43
Amortization of prior service cost (credit)			443				474				(3	)			(3	)
Amortization of net loss			1,487				1,066				128				94
Net benefit cost recognized for financial reporting		$	2,371			$	1,931			$	435			$	421

	Six Months Ended June 30
	2012				2011				2012				2011
									Postretirement Health
(Thousands of Dollars)			Pension Benefits								Care Benefits
Service cost		$	2,284			$	2,136			$	10			$	9
Interest cost			3,835				4,016				538				572
Expected return on plan assets			(5,245	)			(5,742	)			(25	)			(37	)
Amortization of transition obligation			-				-				86				86
Amortization of prior service cost (credit)			886				948				(7	)			(7	)
Amortization of net loss			2,922				2,034				242				182
Net benefit cost recognized for financial reporting		$	4,682			$	3,392			$	844			$	805