Pension Plans and Other Postretirement Benefit Plans (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2012		Dec. 31, 2011		Feb. 21, 2012	Dec. 31, 2010
Pension plans and other postretirement benefit plans
Assets Measured at Fair value			[1]		[1]			[1]
Plan contributions and funding
Motion filed with the Bankruptcy Court to make an accelerated contribution		50
Pension Plans
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		1,445.3		1,250.4			985.1
Plan contributions and funding
Employer contribution		126.8		265.1
U.S. qualified pension plans
Pension plans and other postretirement benefit plans
Target Allocation		100.00%
Percentage of Plan Assets		100.00%		100.00%
Assets Measured at Fair value		1,131.7		955.3			719.3
Expected return on plan assets		6.25%		7.75%
Plan contributions and funding
Employer contribution to fund minimum required payments, approved by Bankruptcy Court						26
Employer accelerated contribution to fund minimum required payments, approved by Bankruptcy Court						83
Employer contribution	109.0	114.9		251.4
U.S. qualified pension plans | U.S. equity securities
Pension plans and other postretirement benefit plans
Target Allocation		16.00%
Percentage of Plan Assets		16.00%		16.00%
U.S. qualified pension plans | Non-U.S. equity securities
Pension plans and other postretirement benefit plans
Target Allocation		8.00%
Percentage of Plan Assets		7.00%		7.00%
U.S. qualified pension plans | Short-term debt securities
Pension plans and other postretirement benefit plans
Target Allocation		3.00%
Percentage of Plan Assets		6.00%		3.00%
U.S. qualified pension plans | Intermediate-term debt securities
Pension plans and other postretirement benefit plans
Target Allocation		33.00%
Percentage of Plan Assets		31.00%		33.00%
U.S. qualified pension plans | Long-term debt securities
Pension plans and other postretirement benefit plans
Target Allocation		34.00%
Percentage of Plan Assets		35.00%		36.00%
U.S. qualified pension plans | Other investments
Pension plans and other postretirement benefit plans
Target Allocation		6.00%
Percentage of Plan Assets		5.00%		5.00%
U.S. qualified pension plans | U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		178.8		153.4
U.S. qualified pension plans | Non-U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		79.2		64.3
U.S. qualified pension plans | Corporate bond group trust funds - intermediate-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		348.4		317.0
U.S. qualified pension plans | Corporate bond group trust funds - long-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		399.4		346.5
U.S. qualified pension plans | Other fixed income group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		36.9		32.4
U.S. qualified pension plans | REIT group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		15.0		12.0
U.S. qualified pension plans | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		58.1		14.7
U.S. qualified pension plans | Annuity and immediate participation contracts
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		15.9		15.0
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Non-U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Corporate bond group trust funds - intermediate-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Corporate bond group trust funds - long-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Other fixed income group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | REIT group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Annuity and immediate participation contracts
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		1,131.7		955.3
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		178.8		153.4
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Non-U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		79.2		64.3
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Corporate bond group trust funds - intermediate-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		348.4		317.0
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Corporate bond group trust funds - long-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		399.4		346.5
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Other fixed income group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		36.9		32.4
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | REIT group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		15.0		12.0
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		58.1		14.7
U.S. qualified pension plans | Significant Other Observable Inputs (Level 2) | Annuity and immediate participation contracts
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		15.9		15.0
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Non-U.S. equity group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Corporate bond group trust funds - intermediate-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Corporate bond group trust funds - long-term
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Other fixed income group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | REIT group trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
U.S. qualified pension plans | Significant Unobservable Inputs (Level 3) | Annuity and immediate participation contracts
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		313.6		295.1			265.8
Percentage of foreign plan assets to global pension assets		22.00%		24.00%
Expected return on plan assets		4.98%		5.96%
Plan contributions and funding
Employer contribution		11.9		13.7
Expected employer contribution for 2012		13
Non-U.S. pension plans | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		301.3		283.5
Non-U.S. pension plans | Government and agency securities
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		2.4		1.9
Non-U.S. pension plans | Corporate bonds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		1.2		1.1
Non-U.S. pension plans | Insurance contracts and other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		8.0		8.0
Non-U.S. pension plans | Cash
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		0.7		0.6
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		0.7		0.6
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Government and agency securities
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Corporate bonds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Insurance contracts and other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Cash
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		0.7		0.6
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		312.9		294.5
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		301.3		283.5
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2) | Government and agency securities
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		2.4		1.9
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2) | Corporate bonds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		1.2		1.1
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2) | Insurance contracts and other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		8.0		8.0
Non-U.S. pension plans | Significant Other Observable Inputs (Level 2) | Cash
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3)
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3) | Common/collective trust funds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3) | Government and agency securities
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3) | Corporate bonds
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3) | Insurance contracts and other investments
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | Significant Unobservable Inputs (Level 3) | Cash
Pension plans and other postretirement benefit plans
Assets Measured at Fair value
Non-U.S. pension plans | United Kingdom
Pension plans and other postretirement benefit plans
Target Allocation		100.00%
Percentage of Plan Assets		100.00%		100.00%
Percentage of specified foreign plan assets to total non -U.S plan assets		82.00%
Expected return on plan assets		4.50%
Non-U.S. pension plans | United Kingdom | Equity securities
Pension plans and other postretirement benefit plans
Target Allocation
Percentage of Plan Assets				8.00%
Non-U.S. pension plans | United Kingdom | Diversified growth funds
Pension plans and other postretirement benefit plans
Target Allocation		12.00%
Percentage of Plan Assets		12.00%
Non-U.S. pension plans | United Kingdom | U.K. gilts
Pension plans and other postretirement benefit plans
Target Allocation		41.00%
Percentage of Plan Assets		41.00%		37.00%
Non-U.S. pension plans | United Kingdom | U.K. corporate bonds
Pension plans and other postretirement benefit plans
Target Allocation		47.00%
Percentage of Plan Assets		47.00%		55.00%
Non-U.S. pension plans | Canada
Pension plans and other postretirement benefit plans
Target Allocation		100.00%
Percentage of Plan Assets		100.00%		100.00%
Percentage of specified foreign plan assets to total non -U.S plan assets		8.00%		8.00%
Expected return on plan assets		7.00%
Non-U.S. pension plans | Canada | Equity securities
Pension plans and other postretirement benefit plans
Target Allocation		60.00%
Percentage of Plan Assets		61.00%		61.00%
Non-U.S. pension plans | Canada | Bonds
Pension plans and other postretirement benefit plans
Target Allocation		40.00%
Percentage of Plan Assets		39.00%		39.00%
Non-U.S. pension plans | Other country
Pension plans and other postretirement benefit plans
Percentage of specified foreign plan assets to total non -U.S plan assets		10.00%
Percentage of individual foreign plan to total foreign plan assets		3.00%		3.00%
Postretirement Benefits Other Than Pensions
Pension plans and other postretirement benefit plans
Assets Measured at Fair value		0		0			0
Plan contributions and funding
Employer contribution		1.3		1.7
Expected employer contribution for 2012		$ 6

[1] Plans intended to be pay-as-you-go.