Document and Entity Information - USD ($)	12 Months Ended
	Sep. 30, 2018	Nov. 16, 2018	Mar. 31, 2018
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Entity Registrant Name	NEW JERSEY RESOURCES CORP
Entity Central Index Key	0000356309
Current Fiscal Year End Date	--09-30
Entity Well-known Seasoned Issuer	Yes
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 3,451,945,383
Entity Common Stock, Shares Outstanding		88,505,199