Income Taxes	3 Months Ended
Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	7. Income Taxes On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act. The Tax Act contains significant revisions to U.S. corporate income tax provisions, including, but not limited to, a reduction of the U.S. corporate statutory tax rate from 35% to 21%, a one-time transition tax on accumulated foreign earnings, an income inclusion of global intangible low-taxed income (“GILTI”), and a new minimum tax, base erosion anti-abuse tax (“BEAT”). In accordance with ASC 740, the Company recorded the effects of the Tax Act during the three months ended December 31, 2017, the period of enactment. The reduction in U.S. corporate statutory tax rate from 35% to 21% is effective January 1, 2018. The Tax Act requires companies with a fiscal year that begins before and ends after the effective date of the rate change to calculate a blended tax rate based on the pro rata number of days in the fiscal year before and after the effective date. As a result, for the fiscal year ending September 30, 2018, the Company’s statutory income tax rate will be 24.5%. For the fiscal year ending September 30, 2019, the Company will be subject to the U.S. corporate statutory tax rate will be 21%. The reduction of the U.S. corporate statutory rate requires the Company to adjust its U.S. deferred tax assets and liabilities using the newly enacted tax rate of 21%. As a result, the Company recorded a provisional U.S. income tax expense of $27 million for the reduction of its net U.S. deferred tax assets as a discrete item for the three months ended December 31, 2017. Since the Company has a fiscal year ending September 30, 2018, and has applied an annual effective tax rate in calculating its income tax provision for the three months ended December 31, 2017, the impact of the U.S. corporate statutory tax rate change will not be finalized until September 30, 2018. Furthermore, the Company has a provisional deferred tax liability of approximately $4 million, after the impact of the newly enacted tax rate, associated with unremitted earnings due to the uncertainty of the treatment of future distributions under the Tax Act. The one-time transition tax on accumulated foreign earnings (“Transition Tax”) would be imposed at a rate of 15.5% for cash and cash equivalents and 8% for illiquid assets. The Company reasonably estimates that there is no income tax impact related to the Transition Tax and recorded no income tax liability for the three months ended December 31, 2017 due to an estimated overall deficit in accumulated foreign earnings. This estimate is provisional since the Company has not obtained and analyzed information necessary to finalize its accounting for the impact of the Transition Tax. The final impacts of the Transition Tax may differ from the estimate due to changes in interpretations of the Tax Act and updates or changes to the information that the Company has used to estimate the transition impact, including, but not limited to, the impacts from changes to foreign earnings estimates, foreign exchange rates, and cash positions of foreign subsidiaries. GILTI and BEAT are effective for the Company for the fiscal year ended September 30, 2019. For the period of enactment, the Company has elected not to adjust its deferred taxes for the impact of GILTI and will consider the impact of GILTI in the specific period in which it occurs. For the three months ended December 31, 2017, the Company recorded an income tax expense of $52 million. The income tax expense for the three months ended December 31, 2017 is greater than the expected income tax expense at the blended statutory tax rate of 24.5% primarily due to a U.S. income tax expense of $27 million arising from a reduction in net U.S. deferred tax assets due to the change in the U.S. statutory tax rate, foreign income taxed at rates higher than the U.S. statutory tax rate, income withholding taxes, foreign losses with no tax benefit and an increase in uncertain tax positions. For the three months ended December 31, 2016, the Company recorded income tax expense of $17 million. The income tax expense for the three months ended December 31, 2016 is higher than the expected income tax expense at the statutory tax rate of 35% primarily due to income withholding taxes, state income taxes, foreign losses with no tax benefit and an increase in uncertain tax positions, partially offset by a reduction in a valuation allowance. The Company has determined that it is reasonably possible that the gross unrecognized tax benefits as of December 31, 2017 could decrease by up to approximately $3 million related to various ongoing audits and settlement discussions in various foreign jurisdictions during the next twelve months.

7. Income Taxes

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act. The Tax Act contains significant revisions to U.S. corporate income tax provisions, including, but not limited to, a reduction of the U.S. corporate statutory tax rate from 35% to 21%, a one-time transition tax on accumulated foreign earnings, an income inclusion of global intangible low-taxed income (“GILTI”), and a new minimum tax, base erosion anti-abuse tax (“BEAT”). In accordance with ASC 740, the Company recorded the effects of the Tax Act during the three months ended December 31, 2017, the period of enactment.

The reduction in U.S. corporate statutory tax rate from 35% to 21% is effective January 1, 2018. The Tax Act requires companies with a fiscal year that begins before and ends after the effective date of the rate change to calculate a blended tax rate based on the pro rata number of days in the fiscal year before and after the effective date. As a result, for the fiscal year ending September 30, 2018, the Company’s statutory income tax rate will be 24.5%. For the fiscal year ending September 30, 2019, the Company will be subject to the U.S. corporate statutory tax rate will be 21%.

The reduction of the U.S. corporate statutory rate requires the Company to adjust its U.S. deferred tax assets and liabilities using the newly enacted tax rate of 21%. As a result, the Company recorded a provisional U.S. income tax expense of $27 million for the reduction of its net U.S. deferred tax assets as a discrete item for the three months ended December 31, 2017. Since the Company has a fiscal year ending September 30, 2018, and has applied an annual effective tax rate in calculating its income tax provision for the three months ended December 31, 2017, the impact of the U.S. corporate statutory tax rate change will not be finalized until September 30, 2018. Furthermore, the Company has a provisional deferred tax liability of approximately $4 million, after the impact of the newly enacted tax rate, associated with unremitted earnings due to the uncertainty of the treatment of future distributions under the Tax Act.

The one-time transition tax on accumulated foreign earnings (“Transition Tax”) would be imposed at a rate of 15.5% for cash and cash equivalents and 8% for illiquid assets. The Company reasonably estimates that there is no income tax impact related to the Transition Tax and recorded no income tax liability for the three months ended December 31, 2017 due to an estimated overall deficit in accumulated foreign earnings. This estimate is provisional since the Company has not obtained and analyzed information necessary to finalize its accounting for the impact of the Transition Tax. The final impacts of the Transition Tax may differ from the estimate due to changes in interpretations of the Tax Act and updates or changes to the information that the Company has used to estimate the transition impact, including, but not limited to, the impacts from changes to foreign earnings estimates, foreign exchange rates, and cash positions of foreign subsidiaries.

GILTI and BEAT are effective for the Company for the fiscal year ended September 30, 2019. For the period of enactment, the Company has elected not to adjust its deferred taxes for the impact of GILTI and will consider the impact of GILTI in the specific period in which it occurs.

For the three months ended December 31, 2017, the Company recorded an income tax expense of $52 million. The income tax expense for the three months ended December 31, 2017 is greater than the expected income tax expense at the blended statutory tax rate of 24.5% primarily due to a U.S. income tax expense of $27 million arising from a reduction in net U.S. deferred tax assets due to the change in the U.S. statutory tax rate, foreign income taxed at rates higher than the U.S. statutory tax rate, income withholding taxes, foreign losses with no tax benefit and an increase in uncertain tax positions.

For the three months ended December 31, 2016, the Company recorded income tax expense of $17 million. The income tax expense for the three months ended December 31, 2016 is higher than the expected income tax expense at the statutory tax rate of 35% primarily due to income withholding taxes, state income taxes, foreign losses with no tax benefit and an increase in uncertain tax positions, partially offset by a reduction in a valuation allowance.

The Company has determined that it is reasonably possible that the gross unrecognized tax benefits as of December 31, 2017 could decrease by up to approximately $3 million related to various ongoing audits and settlement discussions in various foreign jurisdictions during the next twelve months.