Fair Value (Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Millions		Sep. 30, 2020	Dec. 31, 2019
Carrying Amount [Member]
Assets, Fair Value Disclosure [Abstract]
Accounts receivable - noncurrent	[1]	$ 183	$ 98
Liabilities, Fair Value Disclosure [Abstract]
Non-recourse debt		17,377	16,712
Recourse debt		3,969	3,396
Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Value added tax		9	11
Accounts receivable - noncurrent	[1]	296	145
Liabilities, Fair Value Disclosure [Abstract]
Non-recourse debt		18,987	16,579
Recourse debt		2,461	3,529
Level 1 [Member] | Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Accounts receivable - noncurrent		0	0
Liabilities, Fair Value Disclosure [Abstract]
Non-recourse debt		0	0
Recourse debt		0	0
Level 2 [Member] | Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Accounts receivable - noncurrent		0	0
Liabilities, Fair Value Disclosure [Abstract]
Non-recourse debt		16,053	15,804
Recourse debt		2,461	3,529
Level 3 [Member] | Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Accounts receivable - noncurrent	[1]	296	145
Liabilities, Fair Value Disclosure [Abstract]
Non-recourse debt		2,934	775
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 impacted by the Stabilization Fund enacted by the Chilean government, and are included in Other noncurrent assets in the accompanying Condensed Consolidated Balance Sheets. The fair value and carrying amount of these receivables exclude VAT of $9 million and $11 million as of September 30, 2020 and December 31, 2019, respectively.