Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2012

Benefit Plans [Abstract]

Obligations and funded status of pension and other postretirement benefit plans

     The funded status of the Company's pension plans and other postretirement benefit plans at December 31, 2012 and 2011 is as follows:

MINERALS TECHNOLOGIES INC. AND SUBSIDIARY COMPANIESNOTES TO CONSOLIDATED FINANCIAL STATEMENTS

     Obligations and Funded Status

	Pension Benefits						Post-retirement Benefits
Millions of Dollars		2012			2011			2012			2011
Change in benefit obligation
Benefit obligation at beginning of year	$	271.9		$	226.5		$	14.4		$	15.6
Service cost		8.1			7.1			0.6			0.7
Interest cost		11.6			11.6			0.4			0.6
Actuarial (gain) loss		30.4			40.5			(4.2	)		(2.1	)
Benefits paid		(12.5	)		(11.7	)		(0.5	)		(0.5	)
Settlements		(0.6	)		(1.5	)		--			--
Foreign exchange impact		1.9			(0.6	)		--			--
Other		0.6			0.0			--			--
Benefit obligation at end of year	$	311.4		$	271.9		$	10.6		$	14.4

	Pension Benefits						Post-retirement Benefits
Millions of Dollars		2012			2011			2012			2011
Change in plan assets
Fair value of plan assets beginning of year	$	187.5		$	191.6		$	--		$	--
Actual return on plan assets		17.2			3.1			--			--
Employer contributions		16.4			6.1			0.5			0.5
Plan participants' contributions		0.5			0.4			--			--
Benefits paid		(12.5	)		(11.7	)		(0.5	)		(0.5	)
Settlements		(0.6	)		(1.5	)		--			--
Foreign exchange impact		3.5			(0.5	)		--			--
Fair value of plan assets at end of year	$	212.0		$	187.5		$	--		$	--
Funded status	$	(99.4	)	$	(84.4	)	$	10.6		$	(14.4	)

Amounts recognized in the consolidated balance sheet

    Amounts recognized in the consolidated balance sheet consist of:

	Pension Benefits						Post-retirement Benefits
Millions of Dollars		2012			2011			2012			2011
Current liability		(0.3	)		(0.4	)		(1.0	)		(1.2	)
Non-current liability		(99.1	)		(84.0	)		(9.6	)		(13.2	)
Recognized liability	$	(99.4	)	$	(84.4	)	$	(10.6	)	$	(14.4	)

Amounts recognized in accumulated other comprehensive income

     Amounts recognized in accumulated other comprehensive income, net of related tax effects, consist of:

	Pension Benefits				Post-retirement Benefits
Millions of Dollars		2012		2011		2012			2011
Net actuarial loss	$	93.7	$	84.7	$	(10.1	)	$	1.5
Prior service cost		3.0		2.9		(0.8	)		(11.7	)
Amount recognized end of year	$	96.7	$	87.6	$	(10.9	)	$	(10.2	)

Change in plan assets and benefit obligations recognized in other comprehensive income

     Changes in the Plan assets and benefit obligations recognized in other comprehensive income:

(Millions of Dollars)	Pension Benefits			Post Retirement Benefits
Current year actuarial gain (loss)	$	(17.6	)	$	2.7
Amortization of actuarial loss		8.4			(0.1	)
Amortization of prior service credit(gain) loss		0.7			(1.8	)
Total recognized in other comprehensive income	$	(8.5	)	$	0.8

Components of net periodic benefit cost

     The components of net periodic benefit costs are as follows:

	Pension Benefits									Post-retirement Benefits
Millions of Dollars		2012			2011			2010			2012			2011			2010
Service cost	$	8.1		$	7.1		$	6.6		$	0.6		$	0.7		$	0.7
Interest cost		11.6			11.6			11.5			0.4			0.6			0.8
Expected return on plan assets		(13.5	)		(13.8	)		(12.6	)		--			--			--
Amortization of prior service cost		1.2			1.3			1.4			(3.1	)		(3.1	)		(3.1	)
Recognized net actuarial (gain) loss		13.3			8.6			8.4			(0.1	)		0.1			0.4
Settlement /curtailment loss		0.2			0.5			--						--			--
Net periodic benefit cost	$	20.9		$	15.3		$	15.3		$	(2.2	)	$	(1.7	)	$	(1.2	)

Estimated amortization of amounts in other comprehensive income to be recognized in next fiscal year

     The 2013 estimated amortization of amounts in other comprehensive income are as follows:

(Millions of Dollars)	Pension Benefits		Post Retirement Benefits
Amortization of prior service cost	$	1.0	$	(3.1	)
Amortization of net loss		14.1		--
Total costs to be recognized	$	15.1	$	(3.1	)

Weighted average assumptions used to determine net periodic benefit cost and benefit obligation

     The weighted average assumptions used to determine net periodic benefit cost in the accounting for the pension benefit plans and other benefit plans for the years ended December 31, 2012, 2011 and 2010 are as follows:

	2012		2011		2010
Discount rate	4.32	%	5.70	%	5.75	%
Expected return on plan assets	7.06	%	7.25	%	7.40	%
Rate of compensation increase	3.11	%	3.20	%	3.50	%

The weighted average assumptions used to determine benefit obligations for the pension benefit plans and other benefit plans at December 31, 2012, 2011 and 2010 are as follows:

	2012		2011		2010
Discount rate	3.77	%	4.30	%	5.70	%
Rate of compensation increase	3.14	%	3.10	%	3.20	%

Weighted average asset allocation percentages

     The Company's pension plan weighted average asset allocation percentages at December 31, 2012 and 2011 by asset category are as follows:

Asset Category		2012		2011
Equity securities		56.4	%	56.5	%
Fixed income securities		34.9	%	40.8	%
Real estate		0.5	%	0.1	%
Other		8.2	%	2.6	%
	Total	100.0	%	100.0	%

Fair value of plan assets by category

     The Company's pension plan fair values at December 31, 2012 and 2011 by asset category are as follows:

Million of Dollars

Asset Category				2012		2011
Equity securities			$	119.5	$	106.1
Fixed income securities				74.1		76.4
Real estate				1.0		0.2
Other				17.4		4.8
	Total	$		212.0		187.5

Fair value of plan assets by geographic location

     The following table presents domestic and foreign pension plan assets information at December 31, 2012, 2011 and 2010 (the measurement date of pension plan assets):

	U.S. Plans						International Plans
Millions of Dollars		2012		2011		2010		2012		2011		2010
Fair value of plan assets	$	148.2	$	132.2	$	138.1	$	63.8	$	55.3	$	53.5

Defined benefit pension plan assets measured at fair value

The following table summarizes our defined benefit pension plan assets measured at fair value as of December 31, 2012:

Millions of Dollars	Pension Assets at Fair Value as of December 31, 2012
Asset Class		Quoted PricesIn Active Markets forIdentical Assets		Significant OtherObservable Inputs		SignificantUnobservable Inputs		Total
		(Level 1)		(Level 2)		(Level 3)
Equity Securities
US equities	$	104.5		--		--	$	104.5
Non-US equities		15.0		--		--		15.0
Fixed Income Securities
Corporate debt instruments		43.1		31.0		--		74.1
Real estate and otherReal estate and other
Real estate				--		1.0		1.0
Other				--		17.4		17.4
Total Assets	$	162.6	$	31.0	$	18.4	$	212.0

U.S. equities—This class included actively and passively managed common equity securities comprised primarily of large-capitalization stocks with value, core and growth strategies.

Non-U.S. equities—This class included actively managed common equity securities comprised primarily of international large-capitalization stocks.

Fixed income—Thisclass included debt instruments issued by the US Treasury, and corporate debt instruments.

MINERALS TECHNOLOGIES INC. AND SUBSIDIARY COMPANIESNOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The following table summarizes our defined benefit pension plan assets measured at fair value as of December 31, 2011:

Millions of Dollars	Pension Assets at Fair Value as of December 31, 2011
Asset Class		Quoted PricesIn Active Markets forIdentical Assets		Significant OtherObservable Inputs		SignificantUnobservable Inputs		Total
		(Level 1)		(Level 2)		(Level 3)
Equity Securities
US equities	$	72.5		--		--	$	72.5
Non-US equities		33.6		--		--		33.6
Fixed Income Securities
Government treasuries		--		--		--		--
Corporate debt instruments		59.5		16.9		--		76.4
Real estate and otherReal estate and other
Real estate		--		--		0.2		0.2
Other		0.2		--		4.6		4.8
Total Assets	$	165.8	$	16.9	$	4.8	$	187.5

Estimated future benefit payments

     The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid:

Millions of Dollars		PensionBenefits		Other Benefits
2013	$	13.8	$	1.0
2014	$	14.8	$	0.9
2015	$	16.9	$	0.8
2016	$	17.2	$	0.8
2017	$	19.0	$	0.8
2018-2022$	$	98.9	$	4.0