Schedule of Changes in Issued and Outstanding Common Shares and Treasury Stock (Detail) - shares	9 Months Ended		12 Months Ended	36 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Sep. 30, 2016	Jun. 30, 2017
Equity [Abstract]
Balance, beginning of year	32,564,252	32,378,185	32,378,185
Shares issued under share-based compensation plans	532,491		186,067
Balance, end of current period	33,096,743		32,564,252	33,096,743
Balance, beginning of year	(3,135,927)	(2,831,350)	(2,831,350)
Shares purchased	0	(304,577)	(304,577)	(3,135,927)
Balance, end of current period	(3,135,927)		(3,135,927)	(3,135,927)
Shares outstanding, end of period	29,960,816		29,428,325	29,960,816