CONSOLIDATED STATEMENT OF PARTNERS' CAPITAL - USD ($) $ in Millions	Total	Accumulated Other Comprehensive Income (Loss)	Limited Partner [Member]
Balance at Dec. 31, 2015	$ 2,883	$ 2	$ 2,881
Other comprehensive income, net of tax	3	3	0
Net income (loss)	(646)	0	(646)
Distribution to partners	(781)	0	(781)
Unit-based compensation expense	2	0	2
Balance at Dec. 31, 2016	1,461	5	1,456
Other comprehensive income, net of tax	(8)	(8)	0
Non-Cash Equity Contribution	8	0	8
Net income (loss)	(45)	0	(45)
Distribution to partners	(74)	0	(74)
Unit-based compensation expense	3	0	3
Balance at Dec. 31, 2017	1,345	(3)	1,348
Other comprehensive income, net of tax	(42)	(42)	0
Non-Cash Equity Contribution	31	0	31
Net income (loss)	108	0	108
Distribution to partners	(95)	0	(95)
Unit-based compensation expense	3	0	3
Panhandle Merger	(12)	2	(14)
Balance at Dec. 31, 2018	$ 1,362	$ (47)	$ 1,409