Summary Of Significant Accounting Policies (Earnings Per Share Basic And Diluted) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Jan. 02, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Accounting Policies [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,700
Net income (loss)		$ 6,239	$ (54,465)	$ 47,557
Weighted average shares outstanding (in shares)		115,523	114,612	114,775
Dilutive effect of employee stock options, restricted shares and restricted stock units (in shares)		1,833	0	1,237
Diluted weighted average shares outstanding (in shares)		117,356	114,612	116,012
Basic earnings (loss) per share (in USD per share)		$ 0.05	$ (0.48)	$ 0.41
Diluted earnings (loss) per share (in USD per share)		$ 0.05	$ (0.48)	$ 0.41