Nature of Operations and Summary of Significant Accounting Policies	9 Months Ended
Dec. 31, 2014
Notes To Financial Statements [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	Nature of Operations and Summary of Significant Accounting Policies Nature of Operations STERIS Corporation, an Ohio corporation, develops, manufactures and markets infection prevention, contamination control, microbial reduction, and surgical and gastrointestinal support products and services for healthcare, pharmaceutical, scientific, research, industrial, and governmental Customers throughout the world. As used in this Quarterly Report, STERIS Corporation and its subsidiaries together are called “STERIS,” the “Company,” “we,” “us,” or “our,” unless otherwise noted. We operate in three reportable business segments: Healthcare, Life Sciences, and STERIS Isomedix Services (“Isomedix”). We describe our business segments in note 10 to our consolidated financial statements titled, “Business Segment Information.” Our fiscal year ends on March 31. References in this Quarterly Report to a particular “year” or “year-end” mean our fiscal year. The significant accounting policies applied in preparing the accompanying consolidated financial statements of the Company are summarized below: Interim Financial Statements We prepared the accompanying unaudited consolidated financial statements of the Company according to accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and the instructions to the Quarterly Report on Form 10-Q and Rule 10-01 of Regulation S-X. This means that they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. Our unaudited interim consolidated financial statements contain all material adjustments (including normal recurring accruals and adjustments) management believes are necessary to fairly state our financial condition, results of operations, and cash flows for the periods presented. These interim consolidated financial statements should be read together with the consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended March 31, 2014 dated May 29, 2014. The Consolidated Balance Sheet at March 31, 2014 was derived from the audited consolidated financial statements at March 31, 2014, but does not include all of the information and footnotes required by U.S. GAAP for complete financial statements. Principles of Consolidation We use the consolidation method to report our investment in our subsidiaries. Therefore, the accompanying consolidated financial statements include the accounts of the Company and its wholly-owned and majority-owned subsidiaries. We eliminate inter-company accounts and transactions when we consolidate these accounts. Income attributable to non-controlling interests is reported in the "Interest income and miscellaneous expense" line of our Consolidated Statements of Income and is not material. Use of Estimates We make certain estimates and assumptions when preparing financial statements according to U.S. GAAP that affect the reported amounts of assets and liabilities at the financial statement dates and the reported amounts of revenues and expenses during the periods presented. These estimates and assumptions involve judgments with respect to many factors that are difficult to predict and are beyond our control. Actual results could be materially different from these estimates. We revise the estimates and assumptions as new information becomes available. This means that operating results for the three and nine month periods ended December 31, 2014 are not necessarily indicative of results that may be expected for future quarters or for the full fiscal year ending March 31, 2015. Recent Accounting Pronouncements In May 2014, the FASB issued the Accounting Standards Update (ASU) 2014-09 titled "Revenue from Contracts with Customers", superseding Accounting Standards Codification ASC Topic 605, "Revenue Recognition" and most industry-specific guidance throughout the Industry Topics of the Codification. This amended guidance states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance further states in order to achieve that core principle an entity should apply a series of five steps which include: identify the contract(s) with the Customer, identify the performance obligations in the contract, determine the transaction price, allocate the transaction price to the performance obligation in the contract, and recognize revenue when (or as) the entity satisfies a performance obligation. Entities are given the option to apply either a full retrospective with practical expedients or a modified retrospective transition method. ASU 2014-09 will also require additional disclosures in the notes to the consolidated financial statements. The standard update is effective for annual periods beginning after December 15, 2016 and interim periods within that period, early adoption is not permitted. We are currently in the process of evaluating the impact that the standard will have on our consolidated financial position, results of operations and cash flows. A detailed description of our significant and critical accounting policies, estimates, and assumptions is included in our consolidated financial statements included in our Annual Report on Form 10-K for the year ended March 31, 2014 dated May 29, 2014. Our significant and critical accounting policies, estimates, and assumptions have not changed materially from March 31, 2014.

Nature of Operations and Summary of Significant Accounting Policies

Nature of Operations

STERIS Corporation, an Ohio corporation, develops, manufactures and markets infection prevention, contamination control, microbial reduction, and surgical and gastrointestinal support products and services for healthcare, pharmaceutical, scientific, research, industrial, and governmental Customers throughout the world. As used in this Quarterly Report, STERIS Corporation and its subsidiaries together are called “STERIS,” the “Company,” “we,” “us,” or “our,” unless otherwise noted.

We operate in three reportable business segments: Healthcare, Life Sciences, and STERIS Isomedix Services (“Isomedix”). We describe our business segments in note 10 to our consolidated financial statements titled, “Business Segment Information.” Our fiscal year ends on March 31. References in this Quarterly Report to a particular “year” or “year-end” mean our fiscal year. The significant accounting policies applied in preparing the accompanying consolidated financial statements of the Company are summarized below:

Interim Financial Statements

We prepared the accompanying unaudited consolidated financial statements of the Company according to accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and the instructions to the Quarterly Report on Form 10-Q and Rule 10-01 of Regulation S-X. This means that they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. Our unaudited interim consolidated financial statements contain all material adjustments (including normal recurring accruals and adjustments) management believes are necessary to fairly state our financial condition, results of operations, and cash flows for the periods presented.

These interim consolidated financial statements should be read together with the consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended March 31, 2014 dated May 29, 2014. The Consolidated Balance Sheet at March 31, 2014 was derived from the audited consolidated financial statements at March 31, 2014, but does not include all of the information and footnotes required by U.S. GAAP for complete financial statements.

Principles of Consolidation

We use the consolidation method to report our investment in our subsidiaries. Therefore, the accompanying consolidated financial statements include the accounts of the Company and its wholly-owned and majority-owned subsidiaries. We eliminate inter-company accounts and transactions when we consolidate these accounts. Income attributable to non-controlling interests is reported in the "Interest income and miscellaneous expense" line of our Consolidated Statements of Income and is not material.

Use of Estimates

We make certain estimates and assumptions when preparing financial statements according to U.S. GAAP that affect the reported amounts of assets and liabilities at the financial statement dates and the reported amounts of revenues and expenses during the periods presented. These estimates and assumptions involve judgments with respect to many factors that are difficult to predict and are beyond our control. Actual results could be materially different from these estimates. We revise the estimates and assumptions as new information becomes available. This means that operating results for the three and nine month periods ended December 31, 2014 are not necessarily indicative of results that may be expected for future quarters or for the full fiscal year ending March 31, 2015.

Recent Accounting Pronouncements

In May 2014, the FASB issued the Accounting Standards Update (ASU) 2014-09 titled "Revenue from Contracts with Customers", superseding Accounting Standards Codification ASC Topic 605, "Revenue Recognition" and most industry-specific guidance throughout the Industry Topics of the Codification. This amended guidance states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance further states in order to achieve that core principle an entity should apply a series of five steps which include: identify the contract(s) with the Customer, identify the performance obligations in the contract, determine the transaction price, allocate the transaction price to the performance obligation in the contract, and recognize revenue when (or as) the entity satisfies a performance obligation. Entities are given the option to apply either a full retrospective with practical expedients or a modified retrospective transition method. ASU 2014-09 will also require additional disclosures in the notes to the consolidated financial statements. The standard update is effective for annual periods beginning after December 15, 2016 and interim periods within that period, early adoption is not permitted. We are currently in the process of evaluating the impact that the standard will have on our consolidated financial position, results of operations and cash flows.

A detailed description of our significant and critical accounting policies, estimates, and assumptions is included in our consolidated financial statements included in our Annual Report on Form 10-K for the year ended March 31, 2014 dated May 29, 2014. Our significant and critical accounting policies, estimates, and assumptions have not changed materially from March 31, 2014.