Derivative Instruments and Hedging Activities (Details) - Derivatives designated as hedging instruments - Cash flow hedges - Interest Rate Swaps - 3 month LIBOR interest rate swap, cash flow hedge terminated March 2012 - USD ($)	1 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2012
Interest Rate Swap Agreements
Debt issued		$ 400,000,000
Interest rate swap loss amortized as an increase to interest expense over the remaining term of the debt	$ 23,000,000
Other, net
Interest Rate Swap Agreements
Ineffective portion of the cash flow hedges		$ 2,000,000