Basis of Presentation	9 Months Ended
Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation [Text Block]	BASIS OF PRESENTATION The consolidated financial statements include the accounts of Airgas, Inc. and its subsidiaries (“Airgas” or the “Company”). Intercompany accounts and transactions are eliminated in consolidation. The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). These consolidated financial statements do not include all disclosures required for annual financial statements. These consolidated financial statements should be read in conjunction with the complete disclosures contained in the Company’s audited consolidated financial statements for the fiscal year ended March 31, 2013. The preparation of financial statements in accordance with GAAP requires the use of estimates. The consolidated financial statements reflect, in the opinion of management, reasonable estimates and all adjustments necessary to present fairly the Company’s results of operations, financial position and cash flows for the periods presented. The interim operating results are not necessarily indicative of the results to be expected for the entire year. The Company reclassified $3.1 million and $11.9 million out of selling, distribution and administrative expenses into cost of products sold (excluding depreciation) for the three and nine months ended December 31, 2012, respectively, to correct an error in the prior year classification. Consolidated operating income and net earnings for the three and nine months ended December 31, 2012 were not impacted by the correction, and the amounts are not material to either of the impacted line items in the Company’s Consolidated Statement of Earnings for the three and nine months ended December 31, 2012.

BASIS OF PRESENTATION

The consolidated financial statements include the accounts of Airgas, Inc. and its subsidiaries (“Airgas” or the “Company”). Intercompany accounts and transactions are eliminated in consolidation. The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). These consolidated financial statements do not include all disclosures required for annual financial statements. These consolidated financial statements should be read in conjunction with the complete disclosures contained in the Company’s audited consolidated financial statements for the fiscal year ended March 31, 2013.

The preparation of financial statements in accordance with GAAP requires the use of estimates. The consolidated financial statements reflect, in the opinion of management, reasonable estimates and all adjustments necessary to present fairly the Company’s results of operations, financial position and cash flows for the periods presented. The interim operating results are not necessarily indicative of the results to be expected for the entire year.

The Company reclassified $3.1 million and $11.9 million out of selling, distribution and administrative expenses into cost of products sold (excluding depreciation) for the three and nine months ended December 31, 2012, respectively, to correct an error in the prior year classification. Consolidated operating income and net earnings for the three and nine months ended December 31, 2012 were not impacted by the correction, and the amounts are not material to either of the impacted line items in the Company’s Consolidated Statement of Earnings for the three and nine months ended December 31, 2012.