Income Taxes

3 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

INCOME TAXES

Income tax provisions for interim quarterly periods are based on an estimated annual effective income tax rate calculated separately from the effect of significant, infrequent or unusual discrete items related specifically to interim periods. The following summarizes income tax expense and the effective tax rate in each interim period:

	Three months ended December 31
(In millions)	2019			2018
Income tax expense	$	24		$	19
Effective tax rate percentage	24.7		%	26.4		%

The increase in income tax expense over the prior year was principally driven by higher pre-tax earnings, and the lower effective tax rate is attributed to the current year benefit from favorable discrete items compared to unfavorable discrete items in the prior year.