Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016	Apr. 22, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	SWIFT ENERGY CO
Entity Central Index Key	0000351817
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Document Period End Date	Mar. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q1
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		10,000,001	45,112,751