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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section 50
-Paragraph 4C
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Derivative Instruments and Hedging Activities (Details) - Derivatives designated as hedging instruments - Cash flow hedges - Interest Rate Swaps - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2017	Dec. 31, 2012
3 month LIBOR interest rate swap, cash flow hedge terminated March 2012
Interest Rate Swap Agreements
Debt issued			$ 400,000,000
Loss on termination of swaps being amortized	$ 23,000,000
Other, net \| 3 month LIBOR interest rate swap, cash flow hedge terminated March 2012
Interest Rate Swap Agreements
Ineffective portion of the cash flow hedges			$ 2,000,000
Three Month London Interbank Offered Rate
Interest Rate Swap Agreements
Unrealized gain (loss) on interest rate cash flow hedges, AOCI		$ (12,000,000)