Income Taxes	6 Months Ended
Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Effective Tax Rate The effective income tax rate was 27.5% and 33.7% during the quarters ended March 31, 2015 and 2014, respectively and 25.0% and 35.5% during the six months ended March 31, 2015 and 2014, respectively. The provision for income taxes during interim quarterly reporting periods is based on our estimates of the effective tax rates for the respective full fiscal year. The effective tax rate in any quarter can also be affected positively or negatively by adjustments that are required to be reported in the specific quarter of resolution. The decrease in our effective tax rate year over year was primarily due to the retroactive extension of the U.S. Federal Research and Development Credit through 2014, which was enacted during the first quarter of our fiscal 2015, as well as a higher percentage of revenue expected in lower taxing jurisdictions. The total unrecognized tax benefit for uncertain tax positions is estimated to be approximately $5.0 million and $4.6 million at March 31, 2015 and September 30, 2014, respectively. We recognize interest expense related to unrecognized tax benefits and penalties as part of the provision for income taxes in our condensed consolidated statements of income and comprehensive income. We have accrued interest of $0.6 million and $0.5 million, related to unrecognized tax benefits as of March 31, 2015 and September 30, 2014, respectively.

Income Taxes

6 Months Ended

Mar. 31, 2015

Effective Tax Rate

The effective income tax rate was 27.5% and 33.7% during the quarters ended March 31, 2015 and 2014, respectively and 25.0% and 35.5% during the six months ended March 31, 2015 and 2014, respectively. The provision for income taxes during interim quarterly reporting periods is based on our estimates of the effective tax rates for the respective full fiscal year. The effective tax rate in any quarter can also be affected positively or negatively by adjustments that are required to be reported in the specific quarter of resolution. The decrease in our effective tax rate year over year was primarily due to the retroactive extension of the U.S. Federal Research and Development Credit through 2014, which was enacted during the first quarter of our fiscal 2015, as well as a higher percentage of revenue expected in lower taxing jurisdictions.

The total unrecognized tax benefit for uncertain tax positions is estimated to be approximately $5.0 million and $4.6 million at March 31, 2015 and September 30, 2014, respectively. We recognize interest expense related to unrecognized tax benefits and penalties as part of the provision for income taxes in our condensed consolidated statements of income and comprehensive income. We have accrued interest of $0.6 million and $0.5 million, related to unrecognized tax benefits as of March 31, 2015 and September 30, 2014, respectively.