v3.3.1.900

Debt (Textuals) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Feb. 08, 2016
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum Remaining Lease Term |  |  |  | 36 years |  |  |
Lease Assets, Historical Cost |  | $ 877 |  | $ 877 | $ 933 |  |
Lease Assets, Accumulated Depreciation |  | 390 |  | 390 | 395 |  |
Gains (Losses) on Extinguishment of Debt |  |  |  | $ (40) | $ (346) | $ (144) |
First Lien Notes 2023 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed |  |  |  | 10.00% |  |  |
Gains (Losses) on Extinguishment of Debt |  | (7) | $ (19) |  |  |  |
Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Repayment time for drawings under letters of credit |  |  |  | 2 days |  |  |
Excess amount of asset sales requiring mandatory prepayments |  |  |  | $ 3,000 |  |  |
Corporate Revolving Facility [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Applicable margin range percentage above base rate |  |  |  | 1.00% |  |  |
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates |  |  |  | 2.00% |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage |  |  |  | 0.25% |  |  |
Corporate Revolving Facility [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Applicable margin range percentage above base rate |  |  |  | 1.25% |  |  |
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates |  |  |  | 2.25% |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage |  |  |  | 0.50% |  |  |
CDHI [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Letter of Credit Total |  | 300 |  | $ 300 |  |  |
One Month [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 1 month |  |  |
Two Months [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 2 months |  |  |
Three Months [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 3 months |  |  |
Six Months [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 6 months |  |  |
Nine Months [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 9 months |  |  |
Twelve Months [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  | 12 months |  |  |
Federal Funds Effective Rate [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 0.50% |  |  |
Subsequent Event [Member] | Corporate Revolving Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of Credit Facility, Increase (Decrease), Net | $ 178 |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  |  |  |  | $ 1,678
Increase in Letter of Credit Sublimit |  |  |  |  |  |  | 250
Total Letter of Credit Sublimit |  |  |  |  |  |  | $ 1,000
Extension of Line of Credit Revolver | 2 years |  |  |  |  |  |
Granite Ridge Energy LLC [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Proceeds from 2023 First Lien Term Loan utilize for Acquisition of Granite Ridge Energy LLC |  | $ 325 |  | $ 325 |  |  |

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