Income Taxes	6 Months Ended
Mar. 31, 2014
Income Taxes	9. Income Taxes Effective Tax Rate The effective income tax rate was 33.7% and 27.1% during the quarters ended March 31, 2014 and 2013, respectively, and 35.5% and 30.6% during the six months ended March 31, 2014 and 2013, 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. Our effective tax rate year over year was negatively impacted by: the expiration of the U.S. Federal Research and Development credit; a one-time state audit adjustment; an adjustment for deferred tax assets due to a change in the tax rate of one of our international jurisdictions; and a higher percentage of revenue expected in higher taxing jurisdictions. The total unrecognized tax benefit for uncertain tax positions at March 31, 2014 and September 30, 2013 is estimated to be approximately $6.4 million and $9.0 million, 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. As of March 31, 2014 and September 30, 2013, we have accrued interest of $0.4 million and $0.9 million, respectively, related to unrecognized tax benefits.

Income Taxes

6 Months Ended

Mar. 31, 2014

9. Income Taxes

Effective Tax Rate

The effective income tax rate was 33.7% and 27.1% during the quarters ended March 31, 2014 and 2013, respectively, and 35.5% and 30.6% during the six months ended March 31, 2014 and 2013, 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. Our effective tax rate year over year was negatively impacted by: the expiration of the U.S. Federal Research and Development credit; a one-time state audit adjustment; an adjustment for deferred tax assets due to a change in the tax rate of one of our international jurisdictions; and a higher percentage of revenue expected in higher taxing jurisdictions.

The total unrecognized tax benefit for uncertain tax positions at March 31, 2014 and September 30, 2013 is estimated to be approximately $6.4 million and $9.0 million, 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. As of March 31, 2014 and September 30, 2013, we have accrued interest of $0.4 million and $0.9 million, respectively, related to unrecognized tax benefits.