Document And Entity Information	3 Months Ended
	Dec. 31, 2011	Jan. 31, 2012
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	true
Amendment Description	National Fuel Gas Company is filing this Amendment No. 1 (the "Form 10-Q/A") to its Quarterly Report on Form 10-Q for the quarter ended December 31, 2011 (the "Form 10-Q"), filed with the Securities and Exchange Commission on February 3, 2012, for the sole purpose of correcting the Interactive Data File furnished as Exhibit 101. In the previously furnished Interactive Data File, the complete Note 7 – Business Segment Information (under Item 1 – Notes to Condensed Consolidated Financial Statements) was not block-text tagged, although the table within Note 7 was block-text tagged and each amount within Note 7 was tagged separately as required. No other changes have been made to the Form 10-Q. This Form 10-Q/A continues to speak as of the original filing date of the Form 10-Q, does not reflect events that may have occurred subsequent to the original filing date, and does not modify or update any related disclosures made in the Form 10-Q.
Document Period End Date	Dec. 31, 2011
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Entity Registrant Name	NATIONAL FUEL GAS CO
Entity Central Index Key	0000070145
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		83,073,132
Trading Symbol	nfg