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Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Tax Contingency [Line Items]
Income Tax Expense	$ 10	$ 70	$ 160	$ 164
Effective Income Tax Rate Reconciliation, Percent	3.00%	22.00%	16.00%	20.00%
Unrecognized Tax Benefits, Period Increase (Decrease)			$ (8)
Minimum
Income Tax Contingency [Line Items]
Potential decrease of unrecognized tax benefits	$ 20		20
Maximum
Income Tax Contingency [Line Items]
Potential decrease of unrecognized tax benefits	$ 25		$ 25
DCP Midstream, LLC \| Goodwill Impairment
Income Tax Contingency [Line Items]
Income Tax Expense				$ (74)