Document and Entity Information (USD $)	12 Months Ended
	Sep. 30, 2011	Nov. 21, 2011	Mar. 31, 2011
Document Information [Line Items]
Entity Registrant Name	NEW JERSEY RESOURCES CORP
Entity Central Index Key	0000356309
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Current Fiscal Year End Date	--09-30
Entity Common Stock, Shares Outstanding		41,446,786
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	FY
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,753,066,818