Document and Entity Information	6 Months Ended
	Jun. 30, 2013	Jul. 30, 2013
Document Information [Line Items]
Entity Registrant Name	EDISON MISSION ENERGY
Entity Central Index Key	0000930835
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		100
Midwest Generation LLC
Document Information [Line Items]
Entity Registrant Name	MIDWEST GENERATION LLC
Entity Central Index Key	0001134016
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding