Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Entity Registrant Name	TALEN ENERGY CORPORATION
Entity Central Index Key	0001622536
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		128,508,921
Talen Energy Supply
Entity Registrant Name	TALEN ENERGY SUPPLY, LLC
Entity Central Index Key	0001161976
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		0