Income Taxes	3 Months Ended
Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes For interim income tax reporting, the Company estimates its annual effective tax rate and applies it to year-to-date pretax income, excluding unusual or infrequently occurring discrete items. Tax jurisdictions with losses for which tax benefits cannot be realized are excluded. The Company recorded income tax provisions of $1.0 million and $1.7 million for the three months ended December 31, 2017 and 2016, respectively. In December 2017, the Tax Cuts and Jobs Act tax legislation was signed into law, which reduced the U.S. Federal statutory tax rate from 35% to 21%, among other changes. As a result of the enactment of this legislation, the Company’s fiscal 2018 first quarter net loss includes discrete tax expense of $1.2 million from the Company’s net deferred tax assets revaluation based on the enacted tax rate of 21%, as compared with the previous rate of 35%. U.S. tax law requires that taxpayers with a fiscal year beginning before and ending after the effective date of a rate change calculate a blended tax rate for the year based on the pro rata number of days in the year before and after such effective date. As a result, for the fiscal year ending September 30, 2018, our U.S. federal statutory income tax rate is expected to be 24.5%. The effective income tax rate for the three months ended December 31, 2017 and 2016 differs from the U.S. federal statutory tax rate of 24.5% and 35%, respectively, primarily due to operating losses incurred in Ireland, where tax benefits are offset by a valuation allowance, and non-deductible acquired intangible asset amortization, contingent consideration accretion, including fair value adjustments, as well as unrealized foreign currency translation gains and losses on Euro-denominated contingent consideration liabilities. These increases to the effective income tax rate were partially offset by the U.S. federal research and development income tax credit and, in fiscal 2017, the domestic production manufacturing deduction. The effective income tax rate for the three months ended December 31, 2017 and 2016 is also impacted by discrete tax (benefit) expense of $(0.2) million and $0.3 million, respectively, related to expiring stock option awards, and $0.1 million and $0.2 million of state income tax reserve reversals related to the expiration of statutory filing requirements in each respective period. The total amount of unrecognized tax benefits, excluding interest and penalties that, if recognized, would affect the effective tax rate is $1.4 million and $1.2 million as of December 31, 2017 and September 30, 2017, respectively. Currently, the Company does not expect the liability for unrecognized tax benefits to change significantly in the next 12 months with the above balances classified on the condensed consolidated balance sheets in other long-term liabilities. Interest and penalties related to unrecognized tax benefits are recorded in the income tax provision. The Company files income tax returns, including returns for its subsidiaries, in the U.S. federal jurisdiction and in various state jurisdictions as well as several non-U.S. jurisdictions. Uncertain tax positions are related to tax years that remain subject to examination. U.S. income tax returns for years prior to fiscal 2013 are no longer subject to examination by federal tax authorities. For tax returns for state and local jurisdictions, the Company is no longer subject to examination for tax years generally before fiscal 2007. For tax returns for non-U.S. jurisdictions, the Company is no longer subject to income tax examination for years prior to 2012. Additionally, the Company has been indemnified of liability for any taxes relating to Creagh Medical and NorMedix for periods prior to their respective acquisition dates, pursuant to the terms of the related share purchase agreements. As of December 31, 2017 and September 30, 2017 there were no undistributed earnings in foreign subsidiaries. The Internal Revenue Service (“IRS”) commenced an examination of our fiscal 2016 U.S. federal income tax return in the fourth quarter of fiscal 2017. The examination has not been completed.

12. Income Taxes

For interim income tax reporting, the Company estimates its annual effective tax rate and applies it to year-to-date pretax income, excluding unusual or infrequently occurring discrete items. Tax jurisdictions with losses for which tax benefits cannot be realized are excluded. The Company recorded income tax provisions of $1.0 million and $1.7 million for the three months ended December 31, 2017 and 2016, respectively. In December 2017, the Tax Cuts and Jobs Act tax legislation was signed into law, which reduced the U.S. Federal statutory tax rate from 35% to 21%, among other changes. As a result of the enactment of this legislation, the Company’s fiscal 2018 first quarter net loss includes discrete tax expense of $1.2 million from the Company’s net deferred tax assets revaluation based on the enacted tax rate of 21%, as compared with the previous rate of 35%. U.S. tax law requires that taxpayers with a fiscal year beginning before and ending after the effective date of a rate change calculate a blended tax rate for the year based on the pro rata number of days in the year before and after such effective date. As a result, for the fiscal year ending September 30, 2018, our U.S. federal statutory income tax rate is expected to be 24.5%. The effective income tax rate for the three months ended December 31, 2017 and 2016 differs from the U.S. federal statutory tax rate of 24.5% and 35%, respectively, primarily due to operating losses incurred in Ireland, where tax benefits are offset by a valuation allowance, and non-deductible acquired intangible asset amortization, contingent consideration accretion, including fair value adjustments, as well as unrealized foreign currency translation gains and losses on Euro-denominated contingent consideration liabilities. These increases to the effective income tax rate were partially offset by the U.S. federal research and development income tax credit and, in fiscal 2017, the domestic production manufacturing deduction. The effective income tax rate for the three months ended December 31, 2017 and 2016 is also impacted by discrete tax (benefit) expense of $(0.2) million and $0.3 million, respectively, related to expiring stock option awards, and $0.1 million and $0.2 million of state income tax reserve reversals related to the expiration of statutory filing requirements in each respective period.

The total amount of unrecognized tax benefits, excluding interest and penalties that, if recognized, would affect the effective tax rate is $1.4 million and $1.2 million as of December 31, 2017 and September 30, 2017, respectively. Currently, the Company does not expect the liability for unrecognized tax benefits to change significantly in the next 12 months with the above balances classified on the condensed consolidated balance sheets in other long-term liabilities. Interest and penalties related to unrecognized tax benefits are recorded in the income tax provision.

The Company files income tax returns, including returns for its subsidiaries, in the U.S. federal jurisdiction and in various state jurisdictions as well as several non-U.S. jurisdictions. Uncertain tax positions are related to tax years that remain subject to examination. U.S. income tax returns for years prior to fiscal 2013 are no longer subject to examination by federal tax authorities. For tax returns for state and local jurisdictions, the Company is no longer subject to examination for tax years generally before fiscal 2007. For tax returns for non-U.S. jurisdictions, the Company is no longer subject to income tax examination for years prior to 2012. Additionally, the Company has been indemnified of liability for any taxes relating to Creagh Medical and NorMedix for periods prior to their respective acquisition dates, pursuant to the terms of the related share purchase agreements. As of December 31, 2017 and September 30, 2017 there were no undistributed earnings in foreign subsidiaries. The Internal Revenue Service (“IRS”) commenced an examination of our fiscal 2016 U.S. federal income tax return in the fourth quarter of fiscal 2017. The examination has not been completed.