CONSOLIDATED STATEMENTS OF COMMON STOCK EQUITY - USD ($) $ in Thousands		Total	Common Stock	Premium on Common Stock	Accumulated Other Comprehensive (Loss) Income	Treasury Stock And Other	Retained Earnings
Beginning Balance (in shares) at Sep. 30, 2013			83,923,000
Beginning Balance at Sep. 30, 2013		$ 887,384	$ 217,795	$ 194,964	$ (1,621)	$ (128,638)	$ 604,884
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		141,970					141,970
Other comprehensive (loss)		(3,973)			(3,973)
Common stock issued:
Incentive compensation plan (in shares)			171,000
Incentive compensation plan		3,211	$ 428	2,783
Divident reinvestment plan (in shares)	[1]		591,000
Dividend reinvestment plan	[1]	14,226		2,176		12,050
Tax benefits from stock plans		(184)		(184)
Cash dividend declared ($.975 per share in 2016, $.915 per share in 2015, and $.855 per share in 2014)		(72,025)					(72,025)
Treasury stock and other (in shares)			(329,000)
Treasury stock and other		(4,443)				(4,443)
Ending Balance (in shares) at Sep. 30, 2014			84,356,000
Ending Balance at Sep. 30, 2014		966,166	$ 218,223	199,739	(5,594)	(121,031)	674,829
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		180,960					180,960
Other comprehensive (loss)		(3,800)			(3,800)
Common stock issued:
Incentive compensation plan (in shares)			359,000
Incentive compensation plan		5,908	$ 895	5,013
Divident reinvestment plan (in shares)	[1]		1,149,000
Dividend reinvestment plan	[1]	27,538	$ 1,720	6,722		19,096
Tax benefits from stock plans		(1,344)		(1,344)
Cash dividend declared ($.975 per share in 2016, $.915 per share in 2015, and $.855 per share in 2014)		(78,044)					(78,044)
Treasury stock and other (in shares)			(333,000)
Treasury stock and other		$ 9,572		(199)		9,771
Ending Balance (in shares) at Sep. 30, 2015		85,531,423	85,531,000
Ending Balance at Sep. 30, 2015		$ 1,106,956	$ 220,838	209,931	(9,394)	(92,164)	777,745
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		131,672					131,672
Other comprehensive (loss)		(5,761)			(5,761)
Common stock issued:
Incentive compensation plan (in shares)			325,000
Incentive compensation plan		9,399	$ 816	8,583
Divident reinvestment plan (in shares)	[1]		471,000
Dividend reinvestment plan	[1]	16,063		(2,879)		18,942
Cash dividend declared ($.975 per share in 2016, $.915 per share in 2015, and $.855 per share in 2014)		(83,861)					(83,861)
Treasury stock and other (in shares)			(241,000)
Treasury stock and other		$ (7,877)		(55)		(7,822)
Ending Balance (in shares) at Sep. 30, 2016		86,086,355	86,086,000
Ending Balance at Sep. 30, 2016		$ 1,166,591	$ 221,654	$ 215,580	$ (15,155)	$ (81,044)	$ 825,556

[1] The DRP allows NJR, at its option, to use newly issued shares to raise capital. During fiscal 2015, NJR issued approximately 688,000 new shares through the waiver discount feature of its DRP. There were no new shares issued through the waiver discount feature during fiscal 2014 and fiscal 2016.