Earnings Per Share - Weighted Average Common Shares Used in Computations of Basic and Diluted Earnings per Share (Detail) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Average common shares outstanding (shares)	220,807	213,083	215,817	212,411
Dilutive share equivalents from share-based plans (shares)	0	4,289	4,589	4,735
Average common and common equivalent shares outstanding - assuming dilution (shares)	220,807	217,372	220,406	217,146