Basis of Presentation and Accounting Policies (Policies)	6 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Receivables	Receivables Receivables are stated net of an allowance for doubtful accounts of $24.0 million at March 31, 2016 and $22.0 million at September 30, 2015. In addition, receivables are stated net of an allowance for certain customer returns, rebates and incentives of $10.7 million at March 31, 2016 and $9.2 million at September 30, 2015.
Recent accounting pronouncements	Recent Accounting Pronouncements In March 2016, the Financial Accounting Standards Board (FASB) issued a new standard on share-based compensation. Among other changes to the existing guidance, this standard requires entities to record the excess income tax benefit or deficiency from share-based compensation within the income tax provision rather than within additional paid-in capital. This guidance is effective for us for reporting periods beginning no later than October 1, 2017. We are currently evaluating the impact the adoption of this guidance will have on our consolidated financial statements and related disclosures. In February 2016, the FASB issued a new standard on accounting for leases which requires lessees to recognize right-of-use assets and lease liabilities for most leases, among other changes to existing lease accounting guidance. The new standard also requires additional qualitative and quantitative disclosures about leasing activities. This guidance is effective for us for reporting periods beginning October 1, 2019. We are currently evaluating the impact the adoption of this guidance will have on our consolidated financial statements and related disclosures. In November 2015, the FASB issued new guidance that requires all deferred income taxes to be classified on the balance sheet as noncurrent assets or liabilities rather than separating current and noncurrent deferred income taxes based on the classification of the related assets and liabilities. This requirement is effective for us no later than October 1, 2017; however, we elected to adopt earlier as of December 31, 2015. Upon adoption of this guidance we retrospectively reclassified $151.2 million of deferred income taxes from current assets to noncurrent assets at September 30, 2015. In May 2014, the FASB issued a new standard on revenue recognition related to contracts with customers. This standard supersedes nearly all existing revenue recognition guidance and involves a five-step approach to recognizing revenue based on individual performance obligations in a contract. The new standard will also require additional qualitative and quantitative disclosures about contracts with customers, significant judgments made in applying the revenue guidance, and assets recognized from the costs to obtain or fulfill a contract. This guidance is effective for us for reporting periods beginning October 1, 2018. We are currently evaluating the impact the adoption of this guidance will have on our consolidated financial statements and related disclosures.
Product warranty obligations	We record a liability for product warranty obligations at the time of sale to a customer based upon historical warranty experience. Most of our products are covered under a warranty period that runs for twelve months from either the date of sale or installation. We also record a liability for specific warranty matters when they become probable and reasonably estimable.
Income taxes	At the end of each interim period, we estimate a base effective tax rate that we expect for the full fiscal year based on our most recent forecast of pre-tax income, permanent book and tax differences and global tax planning strategies. We use this base rate to provide for income taxes on a year-to-date basis, excluding the effect of significant unusual items and items that are reported net of their related tax effects. We record the tax effect of significant unusual items and items that are reported net of their tax effects in the period in which they occur.

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.