Fair Value (Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015
ASSETS
Non-Recourse Debt		$ 15,792	$ 15,115
Liabilities [Abstract]
Recourse debt		4,671	4,966
Carrying Amount
ASSETS
Accounts receivable - noncurrent	[1]	264	238
Non-Recourse Debt		15,792	15,115
Liabilities [Abstract]
Recourse debt		4,671	4,966
Fair Value
ASSETS
Accounts receivable - noncurrent	[1]	350	310
Non-Recourse Debt		16,188	15,592
Liabilities [Abstract]
Recourse debt		4,899	4,696
Value added tax		24	27
Fair Value | Level 1
ASSETS
Accounts receivable - noncurrent	[1]	0	0
Non-Recourse Debt		0	0
Liabilities [Abstract]
Recourse debt		0	0
Fair Value | Level 2
ASSETS
Accounts receivable - noncurrent	[1]	20	20
Non-Recourse Debt		15,120	13,325
Liabilities [Abstract]
Recourse debt		4,899	4,696
Fair Value | Level 3
ASSETS
Accounts receivable - noncurrent	[1]	330	290
Non-Recourse Debt		1,068	2,267
Liabilities [Abstract]
Recourse debt		$ 0	$ 0

[1] These accounts receivable principally relate to amounts due from CAMMESA, the administrator of the wholesale electricity market in Argentina, and are included in Other noncurrent assets in the accompanying Consolidated Balance Sheets. The fair value and carrying amount of these receivables exclude VAT of $24 million and $27 million as of December 31, 2016 and 2015, respectively.