Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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The cash outflow to pay off borrowing used to receive debt funding on a regular basis with maturities ranging from 5-10 years.

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Debt and Financing Activities - Long Term Debt (Details) £ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2015 GBP (£)	Mar. 31, 2015 USD ($)
Debt Instrument [Line Items]
Long-term debt outstanding			$ 8,711,000,000			$ 9,709,000,000
Repayment of term loan			996,000,000	$ 233,000,000
Repayment of floating rate notes	$ 400,000,000
Bonds
Debt Instrument [Line Items]
Long-term debt outstanding					£ 60	89,000,000
Repayment of term loan		$ 93,000,000
0.95% Notes
Debt Instrument [Line Items]
Repayments of notes			500,000,000
Notes (as a percent)	0.95%
Current Portion of Long-term Debt
Debt Instrument [Line Items]
Long-term debt outstanding			$ 996,000,000			$ 1,529,000,000