CONSOLIDATED STATEMENTS OF MEMBER'S EQUITY - USD ($) $ in Millions	Total	MEMBER'S EQUITY	MEMBER'S EQUITY Cumulative Effect, Period of Adoption, Adjustment	ACCUMULATED OTHER COMPREHENSIVE LOSS
Balance at beginning of period at Dec. 31, 2017		$ 19,254		$ 18
Balance at beginning of period (Accounting Standards Update 2014-09) at Dec. 31, 2017			$ 9
Balance at beginning of period (Accounting Standards Update 2018-02) at Dec. 31, 2017			(6)	6
MEMBER'S EQUITY
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Net income (loss)	$ 341	341
Other comprehensive loss				(195)
Purchase price accounting adjustments		(5)
Distributions		(1,545)
Other		0
Balance at end of period at Dec. 31, 2018		18,048	(39)	(171)
MEMBER'S EQUITY
Member's equity	$ 17,877			(171)
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Net income (loss)	$ (3,201)	(3,201)
Other comprehensive loss				(8)
Distributions		(1,084)
Other		0
Balance at end of period at Dec. 31, 2019		13,724	$ (3)	(179)
MEMBER'S EQUITY
Member's equity	13,545			(179)
Net income (loss)	651	651
Other comprehensive loss				(55)
Distributions		(1,243)
Other		10
Balance at end of period at Dec. 31, 2020		$ 13,139		(234)
MEMBER'S EQUITY
Member's equity	$ 12,905			$ (234)