Area Of Land Sold

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Debt Instrument, Accelerated Maturity Month And Year If Not Amended, Redeemed Or Refinanced

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Debt Instrument, Amount To Be Amended, Redeemed Or Refinanced To Avoid Acceleration

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM format.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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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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Debt (2015 Term Facility - Narrative) (Details) $ in Millions	1 Months Ended			12 Months Ended
	Sep. 30, 2016 USD ($) a	Jul. 31, 2016 USD ($)	Nov. 30, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Payments on long-term debt				$ 1,175	$ 500
Term Loan 1 due December 2020 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Loans payable			$ 750
Debt instrument, term			3 years
Payments on long-term debt	$ 48	$ 375
Maturity date, year and month				2020-12	2018-11
Accelerated maturity date, year and month if not amended, redeemed or refinanced				2019-10
Debt issuance costs				$ 3
2020 Senior Notes [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Payments on long-term debt	$ 48
Maturity date, year and month				2020-01
Amount to be amended, redeemed or refinanced to avoid acceleration				$ 765
Over LIBOR [Member] \| Term Loan 1 due December 2020 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Basis points				2.50%
West Virginia [Member]
Debt Instrument [Line Items]
Area of land sold \| a	55,000