Consolidated Statements of Shareholders' (Deficit) Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Other Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning balance at Nov. 30, 2012	$ (394.3)	$ 5.9	$ 269.6	$ 0.0	$ (183.5)	$ (486.3)
Beginning balance (in shares) at Nov. 30, 2012		58.9
Net (loss) income	162.9				162.9
Amortization of net actuarial losses, net of income taxes	91.3					91.3
Actuarial losses and prior service costs arising during the period, net of income taxes	167.6					167.6
Amortization of prior service credits, net of income taxes	(0.9)					(0.9)
Conversion of debt to common stock	1.6		1.6
Conversion of debt to common stock (in shares)		0.2
Reclassification from redeemable common stock	3.7		3.7
Reclassification from redeemable common stock (in shares)		0.4
Stock-based compensation and shares issued under equity plans, net	5.4		5.4
Stock-based compensation and other, net (in shares)		0.4
Ending balance at Nov. 30, 2013	37.3	$ 5.9	280.3	0.0	(20.6)	(228.3)
Ending balance, (in shares) at Nov. 30, 2013		59.9
Net (loss) income	(2.2)
Amortization of net actuarial losses, net of income taxes	7.7
Ending balance at Feb. 28, 2014	35.5
Beginning balance at Nov. 30, 2013	37.3	$ 5.9	280.3	0.0	(20.6)	(228.3)
Beginning balance (in shares) at Nov. 30, 2013		59.9
Net (loss) income	(51.4)
Amortization of net actuarial losses, net of income taxes	15.5
Ending balance at May. 31, 2014	(60.2)
Beginning balance at Nov. 30, 2013	37.3	$ 5.9	280.3	0.0	(20.6)	(228.3)
Beginning balance (in shares) at Nov. 30, 2013		59.9
Net (loss) income	(61.9)
Amortization of net actuarial losses, net of income taxes	23.2
Ending balance at Aug. 31, 2014	(60.8)
Beginning balance at Nov. 30, 2013	37.3	$ 5.9	280.3	0.0	(20.6)	(228.3)
Beginning balance (in shares) at Nov. 30, 2013		59.9
Net (loss) income	(50.0)				(50.0)
Amortization of net actuarial losses, net of income taxes	31.1					31.1
Actuarial losses and prior service costs arising during the period, net of income taxes	(136.0)					(136.0)
Amortization of prior service credits, net of income taxes	(0.5)					(0.5)
Reclassification from redeemable common stock	(1.4)		(1.4)
Reclassification from redeemable common stock (in shares)		0.1
Tax benefit from shares issued under equity plans	1.3		1.3
Purchase of treasury stock	(64.5)	$ (64.5)		(64.5)
Purchase of treasury stock (in shares)		(3.5)
Stock-based compensation and shares issued under equity plans, net	7.2		7.2
Stock-based compensation and other, net (in shares)		0.4
Ending balance at Nov. 30, 2014	(175.5)	$ 5.9	287.4	(64.5)	(70.6)	(333.7)
Ending balance, (in shares) at Nov. 30, 2014		56.9
Beginning balance at Feb. 28, 2014	35.5
Net (loss) income	(49.2)
Amortization of net actuarial losses, net of income taxes	7.8
Ending balance at May. 31, 2014	(60.2)
Net (loss) income	(10.5)
Amortization of net actuarial losses, net of income taxes	7.7
Ending balance at Aug. 31, 2014	(60.8)
Net (loss) income	11.9
Amortization of net actuarial losses, net of income taxes	7.4
Actuarial losses and prior service costs arising during the period, net of income taxes	(136.0)
Ending balance at Nov. 30, 2014	(175.5)	$ 5.9	287.4	(64.5)	(70.6)	(333.7)
Ending balance, (in shares) at Nov. 30, 2014		56.9
Net (loss) income	(3.3)
Amortization of net actuarial losses, net of income taxes	12.1
Actuarial losses and prior service costs arising during the period, net of income taxes	0.0
Ending balance at Feb. 28, 2015	(128.9)
Beginning balance at Nov. 30, 2014	(175.5)	$ 5.9	287.4	(64.5)	(70.6)	(333.7)
Beginning balance (in shares) at Nov. 30, 2014		56.9
Net (loss) income	14.0
Amortization of net actuarial losses, net of income taxes	24.4
Ending balance at May. 31, 2015	(98.2)
Beginning balance at Nov. 30, 2014	(175.5)	$ 5.9	287.4	(64.5)	(70.6)	(333.7)
Beginning balance (in shares) at Nov. 30, 2014		56.9
Net (loss) income	(23.9)
Amortization of net actuarial losses, net of income taxes	36.2
Ending balance at Aug. 31, 2015	(109.4)
Beginning balance at Nov. 30, 2014	(175.5)	$ 5.9	287.4	(64.5)	(70.6)	(333.7)
Beginning balance (in shares) at Nov. 30, 2014		56.9
Net (loss) income	(16.2)				(16.2)
Amortization of net actuarial losses, net of income taxes	49.4					49.4
Actuarial losses and prior service costs arising during the period, net of income taxes	(56.6)					(56.6)
Amortization of prior service credits, net of income taxes	(0.8)					(0.8)
Conversion of debt to common stock	49.0	$ 0.5	48.5
Conversion of debt to common stock (in shares)		5.5
Reclassification from redeemable common stock	0.7		0.7
Reclassification from redeemable common stock (in shares)		(0.1)
Tax benefit from shares issued under equity plans	2.5		2.5
Repurchase of shares to satisfy tax withholding obligations	(6.7)		(6.7)
Repurchase of shares to satisfy tax withholding obligations (in shares)		(0.3)
Stock-based compensation and shares issued under equity plans, net	7.8	$ 0.1	7.7
Stock-based compensation and other, net (in shares)		0.9
Ending balance at Nov. 30, 2015	(146.4)	$ 6.5	340.1	(64.5)	(86.8)	(341.7)
Ending balance, (in shares) at Nov. 30, 2015		62.9
Beginning balance at Feb. 28, 2015	(128.9)
Net (loss) income	17.3
Amortization of net actuarial losses, net of income taxes	12.3
Ending balance at May. 31, 2015	(98.2)
Net (loss) income	(37.9)
Amortization of net actuarial losses, net of income taxes	11.8
Ending balance at Aug. 31, 2015	(109.4)
Net (loss) income	7.7
Ending balance at Nov. 30, 2015	$ (146.4)	$ 6.5	$ 340.1	$ (64.5)	$ (86.8)	$ (341.7)
Ending balance, (in shares) at Nov. 30, 2015		62.9