Earnings Per Share - Summary of Basic and Diluted EPS (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Mar. 31, 2013		Apr. 01, 2012		Mar. 31, 2013		Apr. 01, 2012
Earnings Per Share [Abstract]
Net (loss) income attributable to common and participating preferred stockholders	$ (45.5)		$ (3.9)		$ 16.5		$ 19.9
Participating shares at end of period:
Common shares outstanding	139,724		139,349		139,724		139,349
Preferred shares (as-converted basis)	62,839		62,215		62,839		62,215
Total	202,563		201,564		202,563		201,564
Percentage of (loss) income allocated to:
Common shares	100.00%		100.00%		69.00%		69.10%
Preferred shares (a)	0.00%	[1]	0.00%	[1]	31.00%	[1]	30.90%	[1]
Net (loss) income attributable to common shares - basic	(45.5)		(3.9)		11.4		13.8
Dilutive adjustments to (loss) income attributable to common shares from assumed conversion of preferred shares, net of tax:
Income allocated to preferred shares in basic calculation					5.1
Reversal of preferred stock dividends and accretion					24.3
Reversal of income related to fair value of preferred stock conversion feature					(29.3)
Net adjustment					0.1
Net (loss) income attributable to common shares - diluted	$ (45.5)		$ (3.9)		$ 11.5		$ 13.8
Weighted-average common shares outstanding - basic	139,724		139,346		139,604		139,346
Dilutive effect of preferred stock					62,839
Dilutive effect of unvested restricted stock and restricted stock units					1,856
Dilutive effect of stock options					592
Weighted-average shares outstanding - diluted	139,724		139,346		204,891		139,346
Net (loss) income per common share attributable to controlling interest:
Basic (in dollars per share)	$ (0.33)		$ (0.03)		$ 0.08		$ 0.10
Diluted (in dollars per share)	$ (0.33)		$ (0.03)		$ 0.06		$ 0.10

[1] Losses are not allocated to the convertible participating preferred shares since they have no contractual obligation to share in such losses.