Fair Value (Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Millions		Dec. 31, 2020	Dec. 31, 2019
Liabilities [Abstract]
Recourse debt		$ 3,447	$ 3,396
Carrying Amount
ASSETS
Accounts receivable - noncurrent	[1]	97	98
Non-Recourse Debt		16,354	16,712
Liabilities [Abstract]
Recourse debt		3,446	3,396
Fair Value
ASSETS
Accounts receivable - noncurrent	[1]	197	145
Non-Recourse Debt		18,403	16,579
Liabilities [Abstract]
Recourse debt		3,677	3,529
Value added tax		4	11
Fair Value | Level 1
ASSETS
Accounts receivable - noncurrent		0	0
Non-Recourse Debt		5	0
Liabilities [Abstract]
Recourse debt		0	0
Fair Value | Level 2
ASSETS
Accounts receivable - noncurrent		0	0
Non-Recourse Debt		15,301	15,804
Liabilities [Abstract]
Recourse debt		3,677	3,529
Fair Value | Level 3
ASSETS
Accounts receivable - noncurrent	[1]	197	145
Non-Recourse Debt		3,097	775
Liabilities [Abstract]
Recourse debt		$ 0	$ 0

[1] These amounts primarily relate to amounts due from CAMMESA, the administrator of the wholesale electricity market in Argentina, and amounts related to green blend and extend agreements in Chile and are included in Other noncurrent assets in the accompanying Consolidated Balance Sheets. The fair value and carrying amount of the Argentina receivables exclude VAT of $4 million and $11 million as of December 31, 2020 and 2019, respectively.